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Mathematics — Learning Path

100% · 311 of 311 chapters

Part 1: FOUNDATIONS 18/18 ▶

1.1 Arithmetic & Number Sense

1.2 Mathematical Thinking

Part 2: ALGEBRA 83/83 ▶

2.1 Fundamentals of Algebra

2.2 Quadratic Equations & Polynomials

31 Quadratic Equations - Introduction
32 Quadratic Formula
33 Discriminant and Nature of Roots
34 Sum and Product of Roots
35 Quadratic Equations - Advanced
36 Common Roots
37 Quadratic Expression and Function
38 Range of Quadratic Expression
39 Location of Roots
40 Quadratic Inequalities
41 Solving Inequalities Using Location of Roots
42 Quadratic in Two Variables
43 Polynomial Equations
44 Remainder and Factor Theorems
45 Cubic Equations
46 Higher Degree Equations
47 Repeated Roots
48 Extraneous and Lost Roots

2.3 Complex Numbers

2.4 Sequences and Series

2.5 Permutations and Combinations

2.6 Binomial Theorem

90 Binomial Theorem for Positive Integer
91 Binomial Coefficients
92 General and Middle Terms
93 Greatest Term
94 Binomial Theorem - Applications
95 Special Expansions
96 Binomial with Complex Numbers
97 Binomial Theorem for Rational Index

2.7 Inequalities

Part 3: FUNCTIONS 22/22 ▶

3.1 Functions - Fundamentals

3.2 Function Operations and Transformations

112 Algebra of Functions
113 Composite Functions
114 Injective and Surjective Nature of Composites
115 Inverse Functions
116 Graph Transformations - Translations
117 Graph Transformations - Scaling
118 Graph Transformations - Reflections
119 Functions of Form max/min

3.3 Standard Functions

Part 4: COORDINATE GEOMETRY 32/32 ▶

4.1 Straight Lines

4.2 Circles

136 Circle - Standard Forms
137 Circle - Special Cases
138 Line and Circle
139 Tangent and Normal to Circle
140 Pair of Tangents and Chord of Contact
141 Family of Circles

4.3 Conics - Parabola

142 Parabola - Introduction
143 Parabola - Position and Parametric Form
144 Parabola - Tangent and Normal
145 Parabola - Advanced

4.4 Conics - Ellipse

146 Ellipse - Introduction
147 Ellipse - Auxiliary Circle and Eccentric Angle
148 Ellipse - Tangent and Normal
149 Ellipse - Advanced

4.5 Conics - Hyperbola

150 Hyperbola - Introduction
151 Hyperbola - Conjugate and Rectangular
152 Hyperbola - Asymptotes
153 Hyperbola - Parametric and Auxiliary Circle
154 Hyperbola - Tangent and Normal
155 Hyperbola - Advanced

Part 5: TRIGONOMETRY 12/12 ▶

156 Trigonometric Ratios
157 Trigonometric Ratios of Any Angle
158 Trigonometric Functions and Graphs
159 Trigonometric Identities
160 Compound Angles
161 Multiple Angles
162 Transformation Formulas
163 Trigonometric Equations
164 Trigonometric Equations - Advanced
165 Inverse Trigonometric Functions
166 Inverse Trigonometric Functions - Properties
167 Euler's Formula

Part 6: VECTORS 10/10 ▶

Part 7: THREE-DIMENSIONAL GEOMETRY 12/12 ▶

178 3D Coordinates
179 Direction Cosines and Ratios
180 Straight Line in 3D - Equations
181 Straight Line in 3D - Angles and Distances
182 Straight Line in 3D - Advanced
183 Plane - Basic Equations
184 Plane - More Forms
185 Angle and Intersection
186 Distance Formulas for Planes
187 Bisector Planes
188 Regular Tetrahedron
189 Sphere

Part 8: MATRICES AND DETERMINANTS 14/14 ▶

Part 9: CALCULUS - LIMITS AND CONTINUITY 14/14 ▶

Part 10: CALCULUS - DIFFERENTIATION 16/16 ▶

218 Differentiation - Introduction
219 Differentiability
220 Reasons for Non-Differentiability
221 Derivatives of Basic Functions
222 Rules of Differentiation
223 Chain Rule
224 Derivatives of Trigonometric Functions
225 Derivatives of Inverse Trigonometric Functions
226 Derivatives of Exponential and Logarithmic Functions
227 Logarithmic Differentiation
228 Implicit Differentiation
229 Parametric Differentiation
230 Differentiation of Functions w.r.t. Functions
231 Higher Order Derivatives
232 Differentiation of Special Functions
233 Functional Equations and Differentiation

Part 11: CALCULUS - APPLICATIONS OF DERIVATIVES 14/14 ▶

234 Tangent and Normal
235 Tangent and Normal - Advanced
236 Rate of Change
237 Approximations
238 Rolle's Theorem
239 Mean Value Theorems
240 Monotonicity
241 Monotonicity - Applications
242 Maxima and Minima - First Derivative Test
243 Maxima and Minima - Second Derivative Test
244 Concavity and Points of Inflection
245 Maxima and Minima - Special Cases
246 Optimization Problems
247 Curve Sketching

Part 12: CALCULUS - INTEGRATION 20/20 ▶

248 Integration - Introduction
249 Basic Integration Formulas
250 Integration by Substitution
251 Special Integrals - Part 1
252 Special Integrals - Part 2
253 Special Integrals - Part 3
254 Integration by Parts
255 Integration by Parts - Special Forms
256 Partial Fractions - Review and Integration
257 Integration by Cancellation
258 Definite Integration - Introduction
259 Fundamental Theorem of Calculus
260 Properties of Definite Integrals
261 Properties - Advanced
262 Definite Integration Techniques
263 Leibniz Rule
264 Definite Integrals - Inequalities
265 Sum of Series Using Integration
266 Improper Integrals
267 Numerical Integration

Part 13: CALCULUS - AREA AND APPLICATIONS 6/6 ▶

Part 14: DIFFERENTIAL EQUATIONS 10/10 ▶

274 Differential Equations - Introduction
275 First Order - Variable Separable
276 First Order - Reducible to Separable
277 First Order - Linear DE
278 First Order - Reducible to Linear
279 First Order - Exact Equations
280 Second Order - Homogeneous
281 Second Order - Non-Homogeneous
282 Applications of DE
283 Orthogonal and Isogonal Trajectories

Part 15: PROBABILITY 14/14 ▶

Part 16: STATISTICS 8/8 ▶

Part appendix: ADDITIONAL ADVANCED TOPICS 6/6 ▶

Physics — Learning Path

100% · 252 of 252 chapters

Part 1: FOUNDATIONS 14/14 ▶

1.1 The Nature of Physics

1.2 Units, Dimensions, and Measurement

1.3 Mathematical Tools for Physics

Part 2: KINEMATICS 16/16 ▶

2.1 Motion in One Dimension

2.2 Motion in Two Dimensions

2.3 Circular Kinematics

Part 3: DYNAMICS — NEWTON'S LAWS 20/20 ▶

3.1 Forces and Newton's Laws

3.2 Friction

3.3 Circular Dynamics

3.4 Constraints and Contact Forces

Part 4: WORK, ENERGY, AND MOMENTUM 18/18 ▶

4.1 Work and Energy

51 Work Done by a Force
52 Work Done by Variable Forces
53 Kinetic Energy and the Work-Energy Theorem
54 Potential Energy
55 Conservation of Mechanical Energy
56 Power

4.2 Conservative Forces and Energy Landscapes

4.3 Linear Momentum and Collisions

4.4 Centre of Mass

Part 5: ROTATIONAL MECHANICS AND GRAVITATION 22/22 ▶

5.1 Rotational Kinematics

5.2 Moment of Inertia

5.3 Torque and Angular Momentum

5.4 Rolling Motion

5.5 Gravitation

Part 6: PROPERTIES OF MATTER 14/14 ▶

6.1 Elasticity

6.2 Fluid Statics

6.3 Fluid Dynamics

100 Equation of Continuity
101 Bernoulli's Principle
102 Applications of Bernoulli's Principle
103 Viscosity and Stokes' Law
104 Reynolds Number and Turbulence

Part 7: OSCILLATIONS AND WAVES 20/20 ▶

7.1 Simple Harmonic Motion

105 Introduction to Simple Harmonic Motion
106 Equation of SHM and Phase
107 Energy in SHM
108 Spring-Mass Systems
109 Simple Pendulum
110 Compound and Torsional Pendulums

7.2 Damped and Forced Oscillations

7.3 Wave Motion

114 Introduction to Waves
115 The Wave Equation
116 Speed of Waves on a String
117 Principle of Superposition
118 Reflection and Transmission of Waves

7.4 Sound Waves

119 Sound Waves — Nature and Propagation
120 Standing Waves and Normal Modes
121 Vibrations of Strings and Pipes
122 Beats
123 Doppler Effect
124 Intensity and Loudness of Sound

Part 8: THERMAL PHYSICS 22/22 ▶

8.1 Heat and Temperature

125 Temperature and Thermometers
126 Thermal Expansion of Solids and Liquids
127 Thermal Expansion of Gases
128 Calorimetry and Specific Heat

8.2 Heat Transfer

8.3 Kinetic Theory of Gases

133 Ideal Gas Laws
134 Kinetic Theory — Pressure and Temperature
135 Degrees of Freedom and Equipartition
136 Mean Free Path
137 Real Gases and van der Waals Equation

8.4 Thermodynamics

138 First Law of Thermodynamics
139 Thermodynamic Processes — Isothermal and Adiabatic
140 Isobaric and Isochoric Processes
141 PV Diagrams and Work
142 Second Law of Thermodynamics
143 Heat Engines and Carnot Cycle

8.5 Phase Transitions and Advanced Topics

Part 9: ELECTROSTATICS 18/18 ▶

9.1 Electric Charge and Coulomb's Law

147 Electric Charge — Properties and Conservation
148 Coulomb's Law
149 Superposition of Electrostatic Forces
150 Electric Field

9.2 Gauss's Law

9.3 Electric Potential

9.4 Capacitors and Dielectrics

Part 10: CURRENT ELECTRICITY 16/16 ▶

10.1 Electric Current and Resistance

165 Electric Current and Drift Velocity
166 Ohm's Law and Resistance
167 Resistivity and Temperature Dependence
168 Combinations of Resistors
169 EMF and Internal Resistance

10.2 Circuit Analysis

170 Kirchhoff's Laws
171 Wheatstone Bridge
172 Meter Bridge and Potentiometer
173 RC Circuits — Charging and Discharging
174 Electrical Energy and Power

10.3 Thermal and Chemical Effects

175 Heating Effect of Current — Joule's Law
176 Thermoelectricity
177 Electrolysis and Faraday's Laws

10.4 Electrical Instruments

Part 11: MAGNETISM AND ELECTROMAGNETIC INDUCTION 22/22 ▶

11.1 Magnetic Effects of Current

11.2 Lorentz Force and Charged Particles

11.3 Magnetism and Magnetic Materials

11.4 Electromagnetic Induction

194 Faraday's Law of Electromagnetic Induction
195 Lenz's Law
196 Motional EMF
197 Self-Inductance and Mutual Inductance
198 Energy Stored in an Inductor

11.5 Alternating Current

199 AC Generation and RMS Values
200 AC Through R, L, and C
201 LCR Series Circuit and Resonance
202 Power in AC Circuits and Transformers

Part 12: ELECTROMAGNETIC WAVES AND OPTICS 20/20 ▶

12.1 Electromagnetic Waves

12.2 Ray Optics

206 Reflection of Light
207 Spherical Mirrors
208 Refraction of Light — Snell's Law
209 Total Internal Reflection
210 Prism and Dispersion
211 Thin Lenses
212 Lensmaker's Equation and Combinations
213 Optical Instruments

12.3 Wave Optics

214 Huygens' Principle
215 Young's Double Slit Experiment
216 Coherence and Conditions for Interference
217 Thin Film Interference
218 Diffraction — Single Slit
219 Polarisation of Light

12.4 Advanced Optics

220 Diffraction Grating
221 Resolving Power of Optical Instruments
222 Scattering of Light

Part 13: MODERN PHYSICS 22/22 ▶

13.1 Dual Nature of Radiation and Matter

223 Photoelectric Effect
224 Photons and Wave-Particle Duality of Light
225 de Broglie Hypothesis
226 Davisson-Germer Experiment

13.2 Atoms

227 Rutherford's Nuclear Model
228 Bohr's Model of the Hydrogen Atom
229 Hydrogen Spectrum and Spectral Series
230 X-Rays
231 Energy Levels and Quantum Numbers

13.3 Nuclear Physics

13.4 Semiconductor Electronics

238 Semiconductors — Intrinsic and Extrinsic
239 The p-n Junction Diode
240 Diode as Rectifier
241 Special Diodes
242 Transistors — Structure and Action
243 Transistor as Amplifier and Switch
244 Logic Gates and Digital Electronics

Part 14: EXPERIMENTAL PHYSICS 6/6 ▶

14.1 Key Experiments and Measurement Techniques

Part 15: SPECIAL TOPICS FOR JEE ADVANCED 2/2 ▶

Chemistry — Learning Path

0% · 1 of 238 chapters

Part 1: FOUNDATIONS OF CHEMISTRY 0/10 ▶

1.1 Some Basic Concepts

1 Chemistry — What It Is and Why It Matters
2 Laws of Chemical Combination
3 Dalton's Atomic Theory and Modern Atoms
4 The Mole Concept
5 Stoichiometry and Chemical Equations

1.2 Redox Reactions

6 Oxidation and Reduction — Electron Transfer
7 Oxidation Numbers
8 Balancing Redox Equations — Half-Reaction Method
9 Electrochemical Series and Displacement Reactions
10 Redox Reactions in Titrimetry

Part 2: ATOMIC STRUCTURE 1/12 ▶

2.1 Subatomic Particles and Early Models

11 Discovery of Subatomic Particles
12 Thomson's and Rutherford's Models
13 Electromagnetic Radiation and Atomic Spectra
14 Planck's Quantum Theory and the Photoelectric Effect

2.2 Bohr Model and Beyond

15 Bohr's Model of the Hydrogen Atom
16 de Broglie, Heisenberg, and the Quantum Revolution
17 Quantum Numbers and Atomic Orbitals
18 Electron Configuration and Periodicity

2.3 Advanced Atomic Structure

19 Effective Nuclear Charge and Shielding
20 Ionisation Enthalpy and Electron Gain Enthalpy
21 Atomic and Ionic Radii
22 Electronegativity and Periodic Trends Summary

Part 3: CHEMICAL BONDING 0/16 ▶

3.1 Ionic and Covalent Bonding

23 Ionic Bonding
24 Covalent Bonding and Lewis Structures
25 Bond Parameters
26 Coordinate (Dative) Bonding and Resonance

3.2 VSEPR Theory and Molecular Geometry

27 VSEPR Theory — Predicting Shapes
28 Molecular Shapes and Polarity
29 Hybridisation

3.3 Molecular Orbital Theory

30 Molecular Orbital Theory — Basics
31 MO Diagrams for Homonuclear Diatomics
32 MO Theory for Heteronuclear Diatomics
33 Metallic Bonding and Band Theory

3.4 Intermolecular Forces

34 Van der Waals Forces
35 Hydrogen Bonding
36 The Hydrogen Bond in Water
37 Polarity and Solubility — Like Dissolves Like
38 Fajan's Rules and Polarisation

Part 4: STATES OF MATTER 0/14 ▶

4.1 Gaseous State

39 Gas Laws — Boyle, Charles, and Avogadro
40 The Ideal Gas Equation
41 Kinetic Molecular Theory of Gases
42 Real Gases — Deviations from Ideal Behaviour
43 Critical Constants and Liquefaction
44 Gas Mixtures and Partial Pressures

4.2 Liquid State

45 Properties of Liquids
46 Vapour Pressure and Clausius-Clapeyron Equation

4.3 Solid State

47 Classification of Solids
48 Crystal Lattices and Unit Cells
49 Cubic Unit Cells — SC, BCC, FCC
50 Close Packing and Voids
51 Crystal Defects
52 Electrical and Magnetic Properties of Solids

Part 5: CHEMICAL THERMODYNAMICS 0/12 ▶

5.1 First Law and Enthalpy

53 Thermodynamic Systems and Processes
54 The First Law of Thermodynamics
55 Enthalpy
56 Standard Enthalpy Changes
57 Hess's Law and Enthalpy Calculations

5.2 Second Law and Gibbs Energy

58 Entropy and the Second Law
59 Gibbs Free Energy
60 Gibbs Energy and Equilibrium
61 Third Law of Thermodynamics

5.3 Thermochemistry Applications

62 Enthalpy of Solution and Dilution
63 Enthalpy of Phase Transitions
64 Spontaneity in Real Chemical Systems

Part 6: CHEMICAL EQUILIBRIUM 0/16 ▶

6.1 Chemical Equilibrium

65 The Equilibrium State
66 The Equilibrium Constant
67 Le Chatelier's Principle
68 Applications of Equilibrium — Industrial Chemistry
69 Relationship Between Kc, Kp, and Kx
70 Reaction Quotient and Predicting Direction

6.2 Ionic Equilibrium

71 Acids and Bases — Definitions
72 Ionisation of Water and the pH Scale
73 Weak Acids and Ka
74 Weak Bases and Kb
75 Polyprotic Acids and Salt Hydrolysis
76 Buffer Solutions
77 Acid-Base Titrations and Indicators
78 Solubility Equilibrium and Ksp
79 Selective Precipitation and Qualitative Analysis
80 Common Ion Effect and Applications

Part 7: SOLUTIONS 0/8 ▶

7.1 Types of Solutions and Concentration

81 Types of Solutions
82 Expressing Concentration
83 Henry's Law and Gas Solubility

7.2 Colligative Properties

84 Raoult's Law and Vapour Pressure Lowering
85 Boiling Point Elevation
86 Freezing Point Depression
87 Osmotic Pressure
88 Van't Hoff Factor and Abnormal Molar Mass

Part 8: ELECTROCHEMISTRY 0/10 ▶

8.1 Electrochemical Cells

89 Galvanic Cells
90 Standard Electrode Potentials
91 The Nernst Equation
92 Batteries and Fuel Cells

8.2 Electrolysis and Conductance

93 Electrolytic Cells
94 Applications of Electrolysis
95 Electrolytic Conductance
96 Variation of Conductivity with Concentration
97 Corrosion
98 Electrochemistry of Cells — Summary and Advanced Problems

Part 9: CHEMICAL KINETICS 0/10 ▶

9.1 Rate of Reaction

99 Rate of a Chemical Reaction
100 Rate Law and Order of Reaction
101 Integrated Rate Laws
102 Half-Life and Reaction Completion

9.2 Temperature and Mechanisms

103 Temperature Dependence — Arrhenius Equation
104 Collision Theory
105 Transition State Theory
106 Reaction Mechanisms
107 Catalysis
108 Catalysis in Industry and Biology

Part 10: SURFACE CHEMISTRY 0/6 ▶

10.1 Adsorption and Catalysis

109 Adsorption
110 Colloids — Classification and Properties
111 Properties of Colloids

10.2 Applied Surface Chemistry

112 Applications of Colloids
113 Emulsions, Gels, and Foams
114 Catalysis at Surfaces

Part 11: CLASSIFICATION OF ELEMENTS AND PERIODICITY 0/6 ▶

11.1 The Periodic Table

115 Development of the Periodic Table
116 Classification of Elements into Blocks
117 Periodic Trends — A Quantitative Summary

11.2 Periodicity in Properties

118 Oxidation States and Valence
119 Oxides and Their Acid-Base Nature
120 Anomalous Properties of the First Element

Part 12: HYDROGEN AND s-BLOCK ELEMENTS 0/8 ▶

12.1 Hydrogen

121 Hydrogen — The First Element
122 Water and Hydrogen Peroxide

12.2 Alkali Metals — Group 1

123 General Properties of Alkali Metals
124 Compounds of Alkali Metals
125 Alkali Metals in Industry and Biology

12.3 Alkaline Earth Metals — Group 2

126 General Properties of Alkaline Earth Metals
127 Compounds of Alkaline Earth Metals
128 Calcium Chemistry and the Lime Cycle

Part 13: p-BLOCK ELEMENTS 0/24 ▶

13.1 Group 13 — Boron Family

129 General Properties of Group 13
130 Boron and Its Compounds
131 Aluminium and Its Compounds
132 Gallium, Indium, and Thallium — Trends

13.2 Group 14 — Carbon Family

133 General Properties of Group 14
134 Carbon — Allotropes and Compounds
135 Silicon and Its Compounds
136 Tin, Lead, and the Inert Pair Effect

13.3 Group 15 — Nitrogen Family

137 General Properties of Group 15
138 Nitrogen and Its Compounds
139 Phosphorus and Its Compounds
140 Arsenic, Antimony, Bismuth — and Group Trends

13.4 Group 16 — Oxygen Family

141 General Properties of Group 16
142 Oxygen and Ozone
143 Sulphur and Its Compounds
144 Selenium, Tellurium, and Group Trends

13.5 Group 17 — Halogens

145 General Properties of Halogens
146 Chlorine and Hydrochloric Acid
147 Interhalogen Compounds and Oxoacids
148 Fluorine, Bromine, and Iodine — Specific Chemistry

13.6 Group 18 — Noble Gases

149 General Properties of Noble Gases
150 Compounds of Noble Gases
151 Applications of Noble Gases
152 Structures and Bonding of Noble Gas Compounds

Part 14: d-BLOCK AND f-BLOCK ELEMENTS 0/8 ▶

14.1 Transition Elements

153 General Properties of Transition Metals
154 Variable Oxidation States and Ionisation
155 Colour, Magnetism, and Complex Formation
156 Important Compounds of Transition Metals
157 Trends Across the First Transition Series

14.2 Inner Transition Elements

158 Lanthanides
159 Actinides
160 f-Block Elements in Everyday Life

Part 15: COORDINATION COMPOUNDS 0/8 ▶

15.1 Fundamentals

161 Coordination Compounds — Introduction
162 Nomenclature of Coordination Compounds
163 Isomerism in Coordination Compounds
164 Chelation and Polydentate Ligands

15.2 Bonding and Applications

165 Valence Bond Theory for Coordination Compounds
166 Crystal Field Theory
167 Colour and Magnetism from Crystal Field Theory
168 Applications of Coordination Chemistry

Part 16: METALLURGY AND QUALITATIVE ANALYSIS 0/8 ▶

16.1 General Principles of Metallurgy

169 Occurrence of Metals and Ores
170 Concentration of Ores
171 Extraction of Metals — Reduction
172 Refining of Metals

16.2 Qualitative Analysis

173 Detection of Acid Radicals (Anions)
174 Detection of Basic Radicals (Cations) — Groups 0–3
175 Detection of Basic Radicals (Cations) — Groups 4–6
176 Qualitative Analysis — Summary and Practice

Part 17: ORGANIC CHEMISTRY — FOUNDATIONS 0/14 ▶

17.1 Introduction and Nomenclature

177 What is Organic Chemistry?
178 IUPAC Nomenclature — Alkanes, Alkenes, Alkynes
179 IUPAC Nomenclature — Functional Groups
180 IUPAC Nomenclature — Cyclic and Aromatic Compounds

17.2 Isomerism

181 Structural Isomerism
182 Geometrical (cis-trans) Isomerism
183 Optical Isomerism and Chirality
184 Optical Activity and Racemic Mixtures
185 Conformational Isomerism

17.3 General Organic Chemistry (GOC)

186 Electronic Effects — Inductive and Resonance
187 Hyperconjugation and Aromaticity
188 Reactive Intermediates — Carbocations and Carbanions
189 Free Radicals and Reaction Mechanisms
190 Acids and Bases in Organic Chemistry

Part 18: HYDROCARBONS 0/10 ▶

18.1 Alkanes

191 Alkanes — Structure and Properties
192 Reactions of Alkanes

18.2 Alkenes

193 Alkenes — Structure and Properties
194 Electrophilic Addition to Alkenes
195 Further Reactions of Alkenes

18.3 Alkynes

196 Alkynes — Structure and Reactions
197 Further Reactions of Alkynes

18.4 Aromatic Hydrocarbons

198 Benzene — Structure and Aromaticity
199 Electrophilic Aromatic Substitution (EAS)
200 Directing Effects in EAS

Part 19: HALOALKANES AND HALOARENES 0/6 ▶

19.1 Haloalkanes

201 Haloalkanes — Preparation and Properties
202 Nucleophilic Substitution — SN1 and SN2
203 Elimination Reactions — E1 and E2
204 Reactions of Haloalkanes — A Summary

19.2 Haloarenes

205 Haloarenes — Properties and Reactions
206 Polyhalogen Compounds

Part 20: OXYGEN-CONTAINING ORGANIC COMPOUNDS 0/14 ▶

20.1 Alcohols and Phenols

207 Alcohols — Classification and Preparation
208 Reactions of Alcohols
209 Phenols
210 Ethers
211 Epoxides

20.2 Aldehydes and Ketones

212 Aldehydes and Ketones — Structure and Preparation
213 Nucleophilic Addition to the Carbonyl Group
214 Aldol and Cannizzaro Reactions
215 Oxidation and Reduction of Carbonyls
216 Alpha-Hydrogen Reactions and Haloform Test

20.3 Carboxylic Acids

217 Carboxylic Acids — Structure and Preparation
218 Reactions of Carboxylic Acids
219 Acid Derivatives — Esters, Anhydrides, Acid Chlorides
220 Dicarboxylic Acids and Hydroxy Acids

Part 21: NITROGEN-CONTAINING ORGANIC COMPOUNDS 0/8 ▶

21.1 Amines

221 Amines — Classification and Preparation
222 Reactions of Amines
223 Diazonium Salts
224 Aromatic Amine Chemistry

21.2 Other Nitrogen Compounds

225 Nitro Compounds
226 Cyanides and Isocyanides
227 Amides
228 Amino Acids and Peptide Bonds (Preview)

Part 22: BIOMOLECULES, POLYMERS, AND APPLIED CHEMISTRY 0/10 ▶

22.1 Biomolecules

229 Carbohydrates
230 Proteins
231 Nucleic Acids
232 Lipids and Vitamins

22.2 Polymers

233 Polymers — Classification and Types
234 Important Polymers
235 Natural and Synthetic Rubber

22.3 Chemistry in Everyday Life

236 Drugs and Medicines
237 Soaps, Detergents, and Cleansing Agents
238 Food Chemistry and Everyday Applications

Databases — Learning Path

100% · 186 of 186 chapters

Part 1: BUILD 1 — A FILE IS A DATABASE 5/5 ▶

1.1 Build 1

Part 2: BUILD 2 — LOG + IN-MEMORY HASH INDEX (BITCASK) 6/6 ▶

2.1 Build 2

Part 3: BUILD 3 — LSM-TREE STORAGE ENGINE 10/10 ▶

3.1 Build 3

Part 4: BUILD 4 — B+ TREE STORAGE ENGINE 10/10 ▶

4.1 Build 4

Part 5: BUILD 5 — WAL AND ARIES-STYLE RECOVERY 8/8 ▶

5.1 Build 5

Part 6: BUILD 6 — SQL AND A QUERY ENGINE 12/12 ▶

6.1 Build 6

Part 7: BUILD 7 — TRANSACTIONS AND ISOLATION 10/10 ▶

7.1 Build 7

Part 8: BUILD 8 — CLIENT-SERVER ARCHITECTURE 5/5 ▶

8.1 Build 8

Part 9: BUILD 9 — REPLICATION (LEADER-FOLLOWER) 8/8 ▶

9.1 Build 9

Part 10: BUILD 10 — LEADERLESS REPLICATION (DYNAMO-STYLE) 10/10 ▶

10.1 Build 10

Part 11: BUILD 11 — WIDE-COLUMN DATA MODELING 6/6 ▶

11.1 Build 11

Part 12: BUILD 12 — SHARDING A RELATIONAL DATABASE 8/8 ▶

12.1 Build 12

Part 13: BUILD 13 — DISTRIBUTED CONSENSUS (RAFT FROM SCRATCH) 10/10 ▶

13.1 Build 13

Part 14: BUILD 14 — DISTRIBUTED TRANSACTIONS & GEO-DISTRIBUTED DBS 10/10 ▶

14.1 Build 14

Part 15: BUILD 15 — COLUMNAR OLAP ENGINE 10/10 ▶

15.1 Build 15

Part 16: BUILD 16 — DATA WAREHOUSES & LAKEHOUSES 8/8 ▶

16.1 Build 16

Part 17: BUILD 17 — DOCUMENT DATABASE (MONGODB-STYLE) 6/6 ▶

17.1 Build 17

Part 18: BUILD 18 — SEARCH ENGINE (LUCENE, ELASTICSEARCH) 8/8 ▶

18.1 Build 18

Part 19: BUILD 19 — VECTOR DATABASE 7/7 ▶

19.1 Build 19

Part 20: BUILD 20 — GRAPH DATABASE 6/6 ▶

20.1 Build 20

Part 21: BUILD 21 — TIME-SERIES DATABASE 5/5 ▶

21.1 Build 21

Part 22: BUILD 22 — IN-MEMORY DATABASES (REDIS, MEMCACHED) 5/5 ▶

22.1 Build 22

Part 23: BUILD 23 — STREAMING DATABASES & CDC 8/8 ▶

23.1 Build 23

Part 24: BUILD 24 — PUTTING IT TOGETHER 5/5 ▶

24.1 Build 24

Data Engineering — Learning Path

100% · 134 of 134 chapters

Part 1: A SCRIPT IS A PIPELINE 5/5 ▶

1.1 Build 1

Part 2: IDEMPOTENCY AND RETRIES 6/6 ▶

2.1 Build 2

Part 3: INCREMENTAL PROCESSING 7/7 ▶

3.1 Build 3

Part 4: A SCHEDULER FROM SCRATCH 10/10 ▶

4.1 Build 4

Part 5: LINEAGE, OBSERVABILITY, DATA CONTRACTS 8/8 ▶

5.1 Build 5

Part 6: COLUMNAR STORAGE AND TABLE FORMATS (producer's view) 10/10 ▶

6.1 Build 6

Part 7: A MESSAGE LOG FROM SCRATCH 8/8 ▶

7.1 Build 7

Part 8: STATEFUL STREAM PROCESSING 10/10 ▶

8.1 Build 8

Part 9: EXACTLY-ONCE FOR REAL 7/7 ▶

9.1 Build 9

Part 10: UNIFIED BATCH AND STREAM 7/7 ▶

10.1 Build 10

Part 11: CHANGE DATA CAPTURE 8/8 ▶

11.1 Build 11

Part 12: LAKEHOUSE AT SCALE 10/10 ▶

12.1 Build 12

Part 13: THE SEMANTIC / METRICS LAYER 7/7 ▶

13.1 Build 13

Part 14: REAL-TIME ANALYTICS SERVING 8/8 ▶

14.1 Build 14

Part 15: FEATURE STORES 6/6 ▶

15.1 Build 15

Part 16: MULTI-TENANCY, GOVERNANCE, COST 8/8 ▶

16.1 Build 16

Part 17: RUNNING DATA ENGINEERING IN PRODUCTION 9/9 ▶

17.1 Build 17

Operating Systems — Learning Path

0% · 0 of 134 chapters

Part 1: THE MACHINE AT BOOT 0/6 ▶

1.1 Build 1

1 What the BIOS/UEFI hands you
2 Real mode, protected mode, long mode
3 Your first kernel: print "hello" from ring 0
4 The GDT, IDT, and other initials you must know
5 The memory map: what's actually where after boot
6 Wall: single task, single address space, no interrupts

Part 2: INTERRUPTS, TIMERS, AND EXCEPTIONS 0/6 ▶

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7 The interrupt vector: hardware's phone call to you
8 PIC → APIC → x2APIC
9 Timers: PIT, HPET, TSC, invariant TSC
10 Exceptions vs interrupts vs syscalls
11 The clock tick and the tickless-kernel debate
12 Wall: interrupts without processes = chaos

Part 3: PROCESSES AND CONTEXT SWITCHING 0/7 ▶

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13 What a process actually is: address space + control state
14 The task struct / PCB
15 Context switch from first principles (registers, stack, kernel entry)
16 fork(), exec(), and their surprising semantics
17 Threads as lightweight processes (or not)
18 Process lifecycle: zombies, orphans, init-as-reaper
19 Wall: N processes, one CPU — who runs?

Part 4: SCHEDULING 0/8 ▶

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20 FIFO and round-robin and their failure modes
21 Priority scheduling and priority inversion
22 MLFQ: the practical workhorse
23 Fair share: CFS from scratch
24 EEVDF: the scheduler that replaced CFS
25 Real-time scheduling: SCHED_FIFO, SCHED_DEADLINE
26 Scheduler tuning and nice levels in production
27 Wall: processes share more than CPU — they share memory

Part 5: VIRTUAL MEMORY 0/10 ▶

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28 Why virtual memory exists (protection, relocation, over-commit)
29 Page tables: the multi-level walk
30 The TLB and why cache misses matter
31 Page faults: minor, major, and COW
32 Demand paging and the working set
33 Page replacement: LRU, clock, ARC
34 Swapping and the OOM killer
35 Huge pages, transparent huge pages
36 Memory compaction and fragmentation
37 Wall: the kernel itself needs an allocator

Part 6: KERNEL MEMORY ALLOCATION 0/6 ▶

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38 The slab allocator
39 Buddy allocator
40 jemalloc / tcmalloc design
41 Arena allocation
42 Kernel memory leaks — how to hunt them
43 Wall: multiple CPUs touching the same memory

Part 7: SYNCHRONIZATION PRIMITIVES 0/8 ▶

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44 Atomic operations at the hardware level
45 Spinlocks: the simplest real lock
46 Mutex and futex design
47 Reader-writer locks
48 Semaphores and condition variables
49 RCU: read-copy-update in the kernel
50 Lockless rings and per-CPU data
51 Wall: locks solve coordination, not communication

Part 8: IPC 0/6 ▶

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52 Pipes and FIFOs
53 Signals: the ugliest IPC, yet ubiquitous
54 Shared memory + semaphores
55 Message queues (System V, POSIX, Mach ports)
56 Unix domain sockets
57 Wall: processes need persistent storage

Part 9: FILESYSTEMS FROM SCRATCH 0/10 ▶

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58 The block device abstraction
59 Inode, superblock, directory — the FFS triad
60 Writing a minimal filesystem (like xv6's)
61 Journaling: how ext3/4 survives crashes
62 Page cache and the read/write path
63 The dentry cache and the VFS layer
64 Extents vs block lists
65 ext4 end-to-end
66 Filesystem checking (fsck) and corruption
67 Wall: journaling has limits — COW is coming

Part 10: ADVANCED FILESYSTEMS 0/7 ▶

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68 Copy-on-write: LFS, WAFL, ZFS lineage
69 ZFS: the everything filesystem
70 Btrfs: ZFS ideas in Linux
71 APFS and modern mobile filesystems
72 F2FS: flash-friendly
73 Distributed filesystems (NFS, Ceph, Lustre) in brief
74 Wall: filesystems assume the block layer is fast

Part 11: THE I/O STACK 0/8 ▶

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75 The block layer and elevators (CFQ, deadline, BFQ, mq-deadline)
76 Multi-queue block layer (blk-mq)
77 io_uring: the new Linux async I/O
78 SPDK and kernel-bypass storage
79 NVMe and the hardware side
80 Direct I/O, O_DIRECT, and when to use it
81 Storage caching layers: bcache, dm-cache
82 Wall: I/O meets networking, and the kernel becomes the bottleneck

Part 12: NETWORK STACK IN THE KERNEL 0/8 ▶

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83 The socket API and where it lives
84 sk_buff: the unit of network data in Linux
85 Netfilter, iptables, nftables, eBPF hooks
86 epoll, kqueue, and the evolution of readiness APIs
87 TCP in the kernel
88 XDP: eBPF at the driver level
89 Kernel bypass: DPDK, AF_XDP, netmap
90 Wall: one kernel, many tenants — isolation becomes the question

Part 13: CONTAINERS AND NAMESPACES 0/7 ▶

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91 Chroot to namespaces: the lineage
92 Linux namespaces: pid, net, mnt, user, uts, ipc
93 cgroups v1 → v2
94 Capabilities and seccomp
95 Building a container in 100 lines of Go
96 runc, containerd, CRI-O internals
97 Wall: namespaces are not a security boundary — VMs are

Part 14: VIRTUALIZATION 0/8 ▶

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98 Full virtualization vs paravirtualization vs containers
99 KVM as a kernel module
100 QEMU + KVM end-to-end
101 Xen architecture
102 VMX/SVM: the hardware assist
103 Nested page tables (EPT / NPT)
104 Firecracker and lightweight VMs
105 Wall: security isn't just isolation — it's every layer

Part 15: OS SECURITY 0/8 ▶

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106 MMU-enforced protection: the foundation
107 SMEP, SMAP, KASLR
108 Capability systems: seL4, Fuchsia
109 Mandatory access control: SELinux, AppArmor
110 Sandboxing: seccomp-bpf, gVisor
111 Rowhammer and other physics-level attacks
112 Spectre/Meltdown and what the OS did
113 Wall: some workloads need bounds we can't usually promise

Part 16: REAL-TIME AND EMBEDDED 0/6 ▶

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114 What "real-time" actually means (hard vs soft)
115 PREEMPT_RT: turning Linux into an RTOS
116 RTOS architectures: FreeRTOS, Zephyr, VxWorks
117 Priority inheritance and priority ceiling
118 Deterministic latency: how to achieve it
119 Wall: alternative kernel designs exist for reasons

Part 17: MODERN OS DIRECTIONS 0/7 ▶

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120 Microkernels: Mach, L4, seL4
121 Unikernels: MirageOS, IncludeOS
122 Exokernels and library OSes
123 Rust in the kernel (and why)
124 The single-address-space OS debate
125 WASM as a substrate for OS-level code
126 Wall: you can't reason about OS without measuring

Part 18: OS OBSERVABILITY AND PERFORMANCE 0/8 ▶

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127 /proc, /sys, and the Unix "everything is a file" philosophy
128 perf: the kernel-aware profiler
129 ftrace and the function graph
130 eBPF deep dive: verifier, maps, helpers
131 BPF tools suite (BCC, bpftrace, libbpf)
132 dtrace for those who had it first
133 Latency histograms in the kernel
134 The 30-year arc: where kernels go next

Networking — Learning Path

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Part 1: BITS ON A WIRE 0/6 ▶

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1 Why layering exists and its limitations
2 Physical signalling: electrical, optical, radio
3 Ethernet framing from scratch
4 MAC addresses and switching
5 Spanning tree and loops
6 Wall: flat L2 doesn't scale to the planet

Part 2: IP AND ROUTING 0/8 ▶

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7 IPv4 packet structure, byte by byte
8 Subnets, CIDR, and address planning
9 Forwarding vs routing
10 ARP and neighbour discovery
11 IPv6: what it changed and what it didn't
12 NAT and its operational realities
13 ICMP: the underrated protocol
14 Wall: IP loses packets — someone has to care

Part 3: TCP FROM SCRATCH 0/10 ▶

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15 The three-way handshake and state machine
16 Sequence numbers, cumulative ACKs, SACK
17 Windows, MSS, and flow control
18 Retransmission: RTO, RTT estimation, Karn's algorithm
19 Connection teardown and TIME_WAIT
20 Zero-copy send, sendfile, splice
21 Small packets: Nagle, delayed ACK, TCP_NODELAY
22 Keepalives, half-open connections
23 BIC, CUBIC, BBR — the congestion control arc
24 Wall: TCP in userspace doesn't saturate modern NICs

Part 4: TCP AT EXTREME SCALE 0/7 ▶

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25 TCP Fast Open (TFO)
26 Multipath TCP
27 TCP offload engines (TOE) and why they died
28 Large segment/receive offload (LSO/LRO, GSO/GRO)
29 BBRv2 and BBRv3 in production
30 Fighting bufferbloat: fq_codel, CAKE
31 Wall: some workloads can't afford TCP's ceremony

Part 5: UDP AND ITS NEW LIFE 0/6 ▶

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32 UDP and when to pick it
33 DNS over UDP: why it works until it doesn't
34 QUIC: UDP with everything bolted on
35 WebRTC and real-time media
36 DTLS
37 Wall: plaintext is dead — enter cryptography

Part 6: TLS AND PKI FROM SCRATCH 0/10 ▶

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38 Symmetric crypto primitives you must know
39 Asymmetric crypto: RSA, ECDSA, Ed25519
40 The TLS 1.2 handshake, step by step
41 TLS 1.3: what got removed and why
42 The certificate chain and trust stores
43 OCSP, CRL, and certificate revocation
44 Certificate Transparency
45 Mutual TLS and its operational cost
46 Post-quantum TLS: Kyber, X25519+Kyber hybrid
47 Wall: per-request crypto is expensive — amortize it

Part 7: HTTP, HTTP/2, HTTP/3 0/8 ▶

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48 HTTP/1.1 and its pipelining mistake
49 HTTP/2: streams, frames, HPACK
50 HTTP/3: streams over QUIC, QPACK
51 Headers, cookies, caching
52 CORS, same-origin, and the browser's security model
53 HTTP semantics vs wire format: RFC 9110 onwards
54 Server-push, early hints, 103
55 Wall: naming is still hard — enter DNS

Part 8: DNS DEEP 0/7 ▶

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56 The hierarchy: root → TLD → authoritative
57 Recursive resolvers and caching
58 Record types beyond A/AAAA/CNAME
59 DNSSEC: chain of trust
60 DNS over HTTPS / TLS / QUIC
61 Anycast DNS
62 Wall: where the packet lands is now a product decision

Part 9: LOAD BALANCING 0/8 ▶

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63 L4 vs L7: the core tradeoff
64 DSR (direct server return)
65 Maglev and consistent hashing
66 Power of two choices
67 Session affinity without breaking failover
68 Health checks: active, passive, outlier detection
69 Global server load balancing (GSLB)
70 Wall: global users need global infrastructure

Part 10: CDN ARCHITECTURE 0/8 ▶

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71 Anycast at planetary scale
72 Edge caches: LRU isn't enough
73 Origin shielding
74 TLS termination at the edge
75 Dynamic content at the edge (Workers, Lambda@Edge)
76 Cache invalidation and the hard problem
77 DDoS absorption at the edge
78 Wall: the edge is only reachable through the Internet

Part 11: BGP AND THE INTERNET 0/8 ▶

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79 Autonomous systems and the global routing table
80 eBGP and iBGP
81 Peering, transit, and the Internet's economics
82 Route leaks and hijacks
83 RPKI and route origin validation
84 BGP convergence and flap damping
85 The Internet topology: Tier 1, IXPs, hyperscale networks
86 Wall: public Internet isn't good enough for datacenter traffic

Part 12: DATACENTER NETWORKING 0/8 ▶

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87 Clos topologies and leaf-spine
88 ECMP and flow hashing
89 RDMA: RoCE vs iWARP vs InfiniBand
90 Lossless Ethernet and PFC
91 Smart NICs and DPUs
92 Hyperscale fabric designs (Jupiter, F16)
93 Optical circuits and beyond
94 Wall: physical networks don't match logical topology

Part 13: NETWORK VIRTUALIZATION 0/7 ▶

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95 VLANs and their limits
96 VXLAN, GRE, Geneve
97 Open vSwitch (OVS)
98 Overlay vs underlay
99 eBPF-based virtual networking (Cilium)
100 Network policy as code
101 Wall: virtual networks need control planes

Part 14: SERVICE MESH AND SIDECARS 0/6 ▶

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102 The sidecar pattern
103 Envoy: the data plane
104 Istio, Linkerd, Consul Connect
105 mTLS everywhere
106 Sidecar-less meshes (Cilium service mesh, ambient Istio)
107 Wall: the userspace stack can't keep up with the NIC

Part 15: HIGH-PERFORMANCE NETWORKING 0/8 ▶

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108 Kernel bypass: DPDK end-to-end
109 AF_XDP and programmable kernels
110 io_uring for networking
111 RDMA verbs and queue pairs
112 GPU-direct networking
113 Programmable switches: P4
114 SmartNIC offloads (Nitro, Mellanox, Pensando)
115 Wall: performance is useless without visibility

Part 16: NETWORK OBSERVABILITY 0/7 ▶

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116 tcpdump and Wireshark: mastery
117 NetFlow, sFlow, IPFIX
118 eBPF for packet tracing (pwru, tcpretrans)
119 Latency: TCP retransmits, spurious timeouts
120 Tail latency in distributed systems: where the network hides
121 Flow logs at scale (VPC flow logs)
122 Wall: everything visible is also attackable

Part 17: NETWORK SECURITY 0/8 ▶

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123 Firewalls: stateful and stateless
124 DDoS: volumetric, protocol, application
125 WAFs and the arms race
126 Zero trust networks
127 WireGuard: the protocol and its design
128 IPSec: the enterprise workhorse
129 Tor and onion routing
130 Wall: where networking is going next

Part 18: FRONTIERS 0/6 ▶

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131 HTTP/3, MASQUE, and proxy protocols
132 IPFS and content-addressed networking
133 Space networking: Starlink, interplanetary
134 Post-quantum networking
135 Programmable planet: network as code
136 The 30-year arc of networking

Distributed Systems — Learning Path

100% · 139 of 139 chapters

Part 1: WHY DISTRIBUTED? 5/5 ▶

1.1 Build 1

Part 2: FAILURE MODELS 6/6 ▶

2.1 Build 2

Part 3: CLOCKS AND TIME 8/8 ▶

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12 Wall clocks and NTP
13 Monotonic clocks
14 Logical clocks (Lamport)
15 Vector clocks
16 Dotted version vectors
17 Hybrid logical clocks (HLC)
18 TrueTime (Spanner) and physical-logical hybrids
19 Wall: without time you still need order

Part 4: MESSAGES AND RPC 8/8 ▶

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Part 5: SERVICE DISCOVERY 6/6 ▶

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Part 6: LOAD BALANCING IN DEPTH 8/8 ▶

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Part 7: RELIABILITY PATTERNS 8/8 ▶

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Part 8: CONSENSUS (systems view) 8/8 ▶

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Part 9: LEADER ELECTION AND LEASES 5/5 ▶

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Part 10: FAILURE DETECTION 7/7 ▶

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63 Heartbeats: the naive approach
64 Phi accrual failure detector
65 SWIM protocol
66 Gossip-based membership (Serf)
67 Lifeguard, Rapid
68 Split-brain and fencing
69 Wall: scaling membership needs gossip

Part 11: GOSSIP PROTOCOLS 6/6 ▶

11.1 Build 11

70 The anti-entropy family
71 Push, pull, push-pull
72 Plumtree (epidemic broadcast trees)
73 HyParView
74 Convergence time analysis
75 Wall: consistency at scale needs new models

Part 12: CONSISTENCY MODELS 8/8 ▶

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Part 13: CRDTs 7/7 ▶

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Part 14: DISTRIBUTED TRANSACTIONS 8/8 ▶

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Part 15: MESSAGING AND STREAMING 8/8 ▶

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Part 16: WORKFLOWS AND ORCHESTRATION 6/6 ▶

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Part 17: GEO-DISTRIBUTION 7/7 ▶

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Part 18: OBSERVABILITY OF DISTRIBUTED SYSTEMS 7/7 ▶

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120 Correlation IDs
121 Distributed tracing (W3C, Dapper, Jaeger)
122 Context propagation across protocols
123 Tail latency aggregation
124 Service dependency graphs
125 Debugging cross-service outages
126 Wall: to trust the system, you must break it

Part 19: CHAOS ENGINEERING 5/5 ▶

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127 The principles (Netflix)
128 Fault injection at the platform level
129 Game days
130 Steady-state hypotheses
131 Wall: every system is unique — study the real ones

Part 20: CASE STUDIES & FRONTIERS 8/8 ▶

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Systems Performance — Learning Path

100% · 120 of 120 chapters

Part 1: THE MODERN CPU 8/8 ▶

1.1 Build 1

Part 2: CACHES AND MEMORY 8/8 ▶

2.1 Build 2

Part 3: NUMA AND MULTI-SOCKET 6/6 ▶

3.1 Build 3

Part 4: BENCHMARKING WITHOUT LYING 8/8 ▶

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Part 5: CPU PROFILING 8/8 ▶

5.1 Build 5

Part 6: eBPF FOR OBSERVABILITY 8/8 ▶

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Part 7: LATENCY AND TAIL LATENCY 8/8 ▶

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Part 8: QUEUEING THEORY FOR ENGINEERS 7/7 ▶

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Part 9: PARALLEL SCALING AND ITS LIMITS 6/6 ▶

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Part 10: I/O PERFORMANCE 8/8 ▶

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Part 11: ALLOCATOR PERFORMANCE 6/6 ▶

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Part 12: HIDDEN COSTS 7/7 ▶

12.1 Build 12

82 Syscall overhead
83 Context switch cost
84 Scheduler latency
85 VDSO and vsyscall
86 The cost of logging
87 The cost of TLS (crypto and memory)
88 Wall: language runtimes have their own performance character

Part 13: LANGUAGE RUNTIME PERFORMANCE 8/8 ▶

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Part 14: CAPACITY PLANNING AND LOAD TESTING 8/8 ▶

14.1 Build 14

97 Headroom, peak, and degraded modes
98 Load testing: wrk, k6, Gatling
99 Chaos under load
100 Shadow traffic
101 Load shedding strategies
102 Autoscaling: metric-based, predictive
103 Capacity at 99.99%
104 Wall: debugging live systems is its own skill

Part 15: PRODUCTION DEBUGGING 8/8 ▶

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Part 16: CASE STUDIES AND WAR STORIES 8/8 ▶

16.1 Build 16

Concurrency & Parallelism — Learning Path

11% · 13 of 114 chapters

Part 1: DEFINITIONS THAT MATTER 5/5 ▶

1.1 Build 1

Part 2: THE MACHINE UNDERNEATH 6/7 ▶

2.1 Build 2

6 Threads and the OS kernel's view
7 User-space schedulers
8 Cores, hyperthreads, and the pretend-ness of parallelism
9 Cache coherence as a concurrency primitive
10 Store buffers and their consequences
11 Instruction reordering by CPU and compiler
12 Wall: you cannot reason without a memory model

Part 3: MEMORY MODELS 1/8 ▶

3.1 Build 3

13 Sequential consistency
14 TSO (x86) in practice
15 ARM/POWER weak memory
16 C++ memory orders (relaxed, acquire, release, seq_cst)
17 The Java Memory Model
18 The Go memory model
19 Rust's borrow checker as a concurrency tool
20 Wall: memory orders are a tool — you need primitives to build with

Part 4: ATOMICS FROM SCRATCH 0/7 ▶

4.1 Build 4

21 Load-link / store-conditional vs CAS
22 Fetch-and-add, xchg
23 Building higher operations from CAS
24 ABA and its workarounds
25 Double-word CAS
26 Atomic flag, atomic counter
27 Wall: atomics alone can't express everything

Part 5: MUTEXES 0/7 ▶

5.1 Build 5

28 The naive spinlock
29 Test-and-test-and-set
30 Ticket locks
31 MCS locks and queue-based locks
32 Futex: kernel-assisted user-space mutex
33 Parking lots (WebKit, Rust std)
34 Wall: mutexes serialize — we need finer-grained

Part 6: READ-HEAVY SYNCHRONIZATION 0/6 ▶

6.1 Build 6

35 Reader-writer locks
36 Seqlocks
37 RCU from scratch
38 Copy-on-write data structures
39 Persistent data structures as a concurrency tool
40 Wall: sometimes you shouldn't lock at all

Part 7: LOCK-FREE DATA STRUCTURES 0/9 ▶

7.1 Build 7

41 The lock-free hierarchy: obstruction-free, lock-free, wait-free
42 Treiber stack
43 Michael-Scott queue
44 Harris list
45 Concurrent hash tables (split-ordered, cuckoo)
46 Concurrent skip lists
47 Linearizability, serializability, and what clients actually see
48 Proving lock-freedom
49 Wall: memory reclamation is the hardest part

Part 8: MEMORY RECLAMATION 0/7 ▶

8.1 Build 8

50 Why reclamation is the real problem
51 Reference counting (and its cycles)
52 Hazard pointers
53 Epoch-based reclamation (EBR)
54 Pointer-based reclamation (PEBR, IBR, NBR)
55 Crossbeam's design
56 Wall: hardware can help

Part 9: HARDWARE TRANSACTIONAL MEMORY 0/5 ▶

9.1 Build 9

57 Intel TSX: the promise
58 Why TSX failed in practice
59 HLE (hardware lock elision)
60 Modern HTM: ARM's TME
61 Wall: software TM is still around

Part 10: SOFTWARE TRANSACTIONAL MEMORY 0/5 ▶

10.1 Build 10

62 STM semantics
63 Optimistic STM (Haskell, Clojure)
64 Why STM didn't take over
65 STM in practice: where it works
66 Wall: async beats threads for I/O-bound workloads

Part 11: ASYNC I/O MODELS 0/8 ▶

11.1 Build 11

67 Callbacks and callback hell
68 Promises and futures
69 async/await: the syntactic miracle
70 Event loops: libuv, Tokio, Node
71 Cooperative scheduling vs preemptive
72 Async cancellation and lifetimes
73 Structured concurrency
74 Wall: async without proper scheduling is broken

Part 12: COROUTINES AND GREEN THREADS 0/7 ▶

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75 Stackful vs stackless coroutines
76 Green threads: Java's Project Loom
77 Go goroutines: GMP model
78 Erlang BEAM processes
79 Kotlin coroutines
80 Virtual threads and JNI pinning
81 Wall: one machine isn't enough

Part 13: WORK-STEALING SCHEDULERS 0/6 ▶

13.1 Build 13

82 Cilk: the original
83 Go runtime scheduler (GMP deep dive)
84 Tokio scheduler
85 Rayon and data parallelism
86 OpenMP
87 Wall: actor-based concurrency is a different mental model

Part 14: ACTOR SYSTEMS 0/7 ▶

14.1 Build 14

88 The actor model: axioms
89 Erlang / OTP supervision trees
90 Akka
91 Orleans and virtual actors
92 Pony's reference capabilities
93 Actors vs CSP (Go channels)
94 Wall: correctness proofs are what you're missing

Part 15: TESTING CONCURRENT CODE 0/8 ▶

15.1 Build 15

95 Why concurrent bugs are the worst
96 Deterministic replay
97 Loom (Rust) and Shuttle
98 DPOR (dynamic partial-order reduction)
99 Jepsen: testing distributed systems from the concurrency angle
100 TLA+ for concurrency
101 Coyote, P, stateright
102 Wall: parallel != concurrent

Part 16: DATA PARALLELISM 0/7 ▶

16.1 Build 16

103 Map, reduce, scan as parallel primitives
104 Parallel prefix sum
105 Parallel sort
106 Parallel hash joins
107 Parallel graph algorithms
108 GPU data parallelism basics
109 Wall: distributed concurrency is a higher level

Part 17: WHERE IT GOES NEXT 1/5 ▶

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110 Structured concurrency as the default
111 Capability-based concurrency (Pony, Rust)
112 Algebraic effects and concurrency
113 Determinism as a correctness tool
114 The 30-year arc

Observability — Learning Path

100% · 114 of 114 chapters

Part 1: THE THREE PILLARS, HONESTLY 5/5 ▶

1.1 Build 1

Part 2: METRICS STORAGE 8/8 ▶

2.1 Build 2

Part 3: LOGS 7/7 ▶

3.1 Build 3

Part 4: DISTRIBUTED TRACING 9/9 ▶

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Part 5: SAMPLING 6/6 ▶

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Part 6: CARDINALITY 6/6 ▶

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Part 7: TIME-SERIES COMPRESSION 6/6 ▶

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Part 8: eBPF-BASED OBSERVABILITY 7/7 ▶

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Part 9: CONTINUOUS PROFILING 7/7 ▶

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Part 10: SLOs AND ERROR BUDGETS 7/7 ▶

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Part 11: ALERTING DESIGN 7/7 ▶

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Part 12: DASHBOARDS THAT MATTER 6/6 ▶

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Part 13: CORRELATION ACROSS PILLARS 7/7 ▶

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Part 14: OPENTELEMETRY INTERNALS 8/8 ▶

14.1 Build 14

89 The data model
90 SDKs vs API
91 The Collector: receivers, processors, exporters
92 Auto-instrumentation
93 Semantic conventions
94 The OTLP protocol
95 Building custom instrumentation
96 Wall: observability for data and ML is different

Part 15: OBSERVABILITY FOR DATA AND ML 6/6 ▶

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Part 16: COST AND RETENTION 7/7 ▶

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Part 17: OBSERVABILITY AS A DISCIPLINE 5/5 ▶

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110 Building the team
111 Playbooks, post-mortems, and blameless culture
112 Incident response tooling
113 The observability maturity model
114 The 30-year arc

Compilers & Runtimes — Learning Path

0% · 1 of 125 chapters

Part 1: LEXING 0/5 ▶

1.1 Build 1

1 What a compiler actually does
2 Handwritten lexers
3 Regular languages and NFA/DFA construction
4 Lex/Flex and lexer generators
5 Wall: tokens without structure is just noise

Part 2: PARSING 0/8 ▶

2.1 Build 2

6 Grammars: BNF, EBNF, PEG
7 Recursive descent (the go-to)
8 Pratt parsers and operator precedence
9 LL(k), LALR, LR
10 PEG and packrat parsing
11 Error recovery
12 Incremental parsing (tree-sitter)
13 Wall: a parse tree isn't what you want

Part 3: AST AND SEMANTIC ANALYSIS 0/7 ▶

3.1 Build 3

14 AST design
15 The visitor pattern and tree walking
16 Scopes and symbol tables
17 Name resolution
18 Constant folding at the AST level
19 Desugaring
20 Wall: untyped trees can't be trusted

Part 4: TYPE SYSTEMS BASICS 0/8 ▶

4.1 Build 4

21 Static vs dynamic types
22 Structural vs nominal typing
23 Subtyping and variance
24 Parametric polymorphism
25 Type checking vs type inference
26 Unification
27 Hindley-Milner type inference
28 Wall: inference is one thing; expressive types are another

Part 5: ADVANCED TYPE SYSTEMS 0/8 ▶

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29 Rank-N types
30 Type classes and traits
31 Linear types
32 Affine types (Rust's ownership)
33 Dependent types (Idris, Agda, Lean)
34 Effect systems
35 Gradual typing (TypeScript, Hack, mypy)
36 Wall: after types, we lower to IR

Part 6: INTERMEDIATE REPRESENTATIONS 0/7 ▶

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37 Three-address code
38 SSA form
39 CPS (continuation-passing style)
40 ANF (A-normal form)
41 MLIR: multi-level IR
42 LLVM IR in detail
43 Wall: IR lets you optimize

Part 7: OPTIMIZATIONS 0/10 ▶

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44 Constant folding and propagation
45 Dead code elimination
46 Common subexpression elimination
47 Loop optimizations: LICM, unrolling, fusion
48 Inlining and its pitfalls
49 Escape analysis
50 Tail-call optimization
51 Auto-vectorization
52 Profile-guided optimization
53 Wall: now we need to emit real code

Part 8: REGISTER ALLOCATION 0/6 ▶

8.1 Build 8

54 Liveness analysis
55 Graph coloring allocation
56 Linear scan allocation
57 Spilling and rematerialization
58 Register pressure in SSA
59 Wall: registers are only half of codegen

Part 9: CODE GENERATION 0/7 ▶

9.1 Build 9

60 Instruction selection (tiling, DAG matching)
61 Instruction scheduling
62 Peephole optimizations
63 ABIs and calling conventions
64 Debug info (DWARF)
65 Targeting x86, ARM, WASM
66 Wall: a .o file isn't a program

Part 10: LINKING AND LOADING 0/6 ▶

10.1 Build 10

67 ELF, Mach-O, PE
68 Static vs dynamic linking
69 Relocations
70 Position-independent code
71 LTO (link-time optimization)
72 Wall: languages with automatic memory need a runtime

Part 11: GARBAGE COLLECTION 0/10 ▶

11.1 Build 11

73 Reference counting
74 Mark-and-sweep
75 Copying and semi-space
76 Generational GC
77 Concurrent GC
78 Incremental GC
79 Region-based memory
80 ZGC, Shenandoah, G1
81 Go's GC: tri-color, concurrent, low-latency
82 Wall: not every language should have a GC

Part 12: MEMORY MANAGEMENT WITHOUT GC 0/6 ▶

12.1 Build 12

83 Manual (C)
84 Smart pointers (C++ unique_ptr, shared_ptr)
85 Ownership and borrowing (Rust)
86 ARC (Swift, Objective-C)
87 Arenas and bump allocators
88 Wall: interpretation is slow — JIT time

Part 13: INTERPRETERS AND JITS 0/8 ▶

13.1 Build 13

89 Tree-walking interpreter
90 Bytecode and stack machines
91 Register-based VMs (Lua, Dalvik)
92 Threaded code and computed goto
93 Baseline JIT
94 Optimizing JIT (tiers, speculation)
95 Deoptimization and on-stack replacement
96 Wall: runtimes are programs too

Part 14: LANGUAGE RUNTIMES 0/8 ▶

14.1 Build 14

97 The runtime's responsibilities
98 Scheduling (green threads, goroutines)
99 I/O integration (epoll, io_uring)
100 Finalizers and cleanup
101 Reflection and introspection
102 FFI: calling C
103 Runtime-language coupling (why V8 ≠ ECMAScript)
104 Wall: industrial compilers are their own world

Part 15: LLVM DEEP DIVE 0/7 ▶

15.1 Build 15

105 The LLVM project history
106 The IR as a first-class artifact
107 Pass manager design
108 Target description and TableGen
109 Clang's frontend
110 MLIR and multi-level IR
111 Wall: academic compilers play differently

Part 16: STUDYING REAL COMPILERS 0/8 ▶

16.1 Build 16

112 GCC: architecture and history
113 Clang/LLVM
114 HotSpot JVM
115 V8 (TurboFan, Maglev, Sparkplug, Ignition)
116 Go compiler
117 Rust compiler (rustc)
118 OCaml and MLs
119 Wall: where compilers go next

Part 17: FRONTIERS 1/6 ▶

17.1 Build 17

120 Separation compilation and incremental builds
121 Parallel compilation
122 WASM and the universal target
123 eBPF as a mini-compiler target
124 Verified compilers (CompCert)
125 The 30-year arc

Quantum Computing — Learning Path

100% · 211 of 211 chapters

Part 1: SETTING THE STAGE 3/3 ▶

1.1 Why Quantum Computing Exists

Part 2: DIRAC NOTATION AND TENSOR PRODUCTS 6/6 ▶

2.1 Dirac Notation

2.2 Tensor Products

Part 3: QUANTUM MECHANICS FOR COMPUTER SCIENTISTS 12/12 ▶

3.1 The Rules

3.2 Puzzles and Pitfalls

3.3 Entanglement and Its Consequences

Part 4: THE QUBIT AND SINGLE-QUBIT GATES 10/10 ▶

4.1 The Gate Zoo

4.2 Working With Single Qubits

Part 5: MULTI-QUBIT SYSTEMS 10/10 ▶

5.1 Two Qubits and Beyond

5.2 Entangled States and Universal Sets

Part 6: QUANTUM CIRCUITS 8/8 ▶

6.1 Circuit Basics

6.2 Measurement and Control

Part 7: FOUNDATIONAL PROTOCOLS 8/8 ▶

7.1 Teleportation and Coding

7.2 Games and Early Applications

Part 8: EARLY QUANTUM ALGORITHMS 8/8 ▶

8.1 The Oracle Model and First Algorithms

8.2 Toward Shor

Part 9: QUANTUM FOURIER TRANSFORM 8/8 ▶

9.1 The Quantum Fourier Transform

9.2 Phase Estimation

Part 10: SHOR'S ALGORITHM 10/10 ▶

10.1 From Factoring to Period Finding

10.2 The Full Algorithm

Part 11: GROVER AND AMPLITUDE AMPLIFICATION 10/10 ▶

11.1 Unstructured Search

11.2 Generalizations and Limits

Part 12: QUANTUM COMPLEXITY THEORY 10/10 ▶

12.1 Classes and Relations

12.2 Advantage and Supremacy

Part 13: DENSITY MATRICES AND QUANTUM CHANNELS 10/10 ▶

13.1 Density Matrices

13.2 Quantum Channels

Part 14: QUANTUM ERROR CORRECTION 15/15 ▶

14.1 Why and How

14.2 Stabilizer Formalism

14.3 Surface Codes and Fault Tolerance

125 Toric and Surface Codes
126 Threshold Theorem
127 Fault-Tolerant Gates and Magic States
128 Logical Qubits in Practice

Part 15: HAMILTONIAN SIMULATION 8/8 ▶

15.1 Simulation Methods

15.2 Advanced Techniques and Applications

Part 16: NISQ-ERA ALGORITHMS 14/14 ▶

16.1 The NISQ Paradigm

16.2 VQE, QAOA, and Quantum ML

16.3 Linear Systems and the Reality Check

Part 17: QUANTUM CRYPTOGRAPHY AND POST-QUANTUM CRYPTO 11/11 ▶

17.1 Quantum Key Distribution

17.2 Post-Quantum Cryptography

Part 18: PHYSICAL IMPLEMENTATIONS 14/14 ▶

18.1 Fundamentals

162 DiVincenzo's Criteria
163 Decoherence T1 and T2

18.2 The Platforms

18.3 Benchmarking and the Landscape

Part 19: ALTERNATIVE COMPUTATIONAL MODELS 12/12 ▶

19.1 Measurement-Based and Adiabatic

176 Measurement-Based Quantum Computing
177 Preparing Cluster States
178 Adiabatic Quantum Computing
179 Equivalence of Adiabatic and Circuit

19.2 Annealing and Walks

19.3 Topological and Continuous-Variable

Part 20: QUANTUM INFORMATION THEORY 12/12 ▶

20.1 Quantum Entropy

20.2 Capacities and Theorems

20.3 Entanglement and the Quantum Internet

Part 21: FRONTIERS AND HOW WE GOT HERE 12/12 ▶

21.1 The 2026 Landscape

21.2 Where to Go Next

21.3 How We Got Here