Cheat Sheets

One-page revision cheat sheets per category — key points and code from every topic, ready to download as a PDF or a shareable Instagram carousel. Free.

247 cheat sheets

Math for AI

High-School Refresher

3 topics

Linear Algebra

7 topics

Calculus

4 topics

Probability & Statistics

5 topics

Optimization

3 topics

Information Theory

2 topics

Discrete Math & Graphs

2 topics

Math Behind Neural Nets & LLMs

2 topics

JavaScript & TypeScript

Language Core

8 topics

Working with Data

6 topics

Async

8 topics

The Browser

8 topics

TypeScript

12 topics

Tooling

5 topics

Quality

5 topics

React

Fundamentals

7 topics

State & Effects

9 topics

Data

8 topics

Forms

6 topics

Routing

5 topics

Patterns

7 topics

Performance

4 topics

Testing

4 topics

HTML, CSS & Responsive

Semantic HTML

5 topics

CSS Fundamentals

6 topics

Layout

6 topics

Responsive

4 topics

Accessibility

5 topics

Full-Stack Integration

CORS

2 topics

Auth in the Browser

4 topics

Calling Your API

4 topics

Across the Boundary

3 topics

Environment & Config

2 topics

Deploying Both

3 topics

Next.js

Foundations

7 topics

Data & Caching

8 topics

Mutations

5 topics

UX & Assets

6 topics

Auth & Security

5 topics

Production

9 topics

Python A–Z

Fundamentals

6 topics

Control Flow

3 topics

Functions

4 topics

Data Structures

6 topics

OOP

6 topics

Errors & Files

4 topics

Iterators & Decorators

4 topics

Modern Python

3 topics

Stdlib Power Tools

5 topics

Important Libraries

6 topics

Concurrency

4 topics

Packaging & venv

2 topics

Internals & Performance

3 topics

FastAPI

Fundamentals

6 topics

Requests & Validation

4 topics

Routing & Structure

3 topics

Dependency Injection

3 topics

Databases

5 topics

Auth & Security

4 topics

Middleware & CORS

3 topics

Async & Performance

3 topics

Background & WebSockets

3 topics

Testing

3 topics

Deployment

3 topics

Git

Beginner

5 topics

Intermediate

4 topics

Advanced

6 topics

Docker

Fundamentals

3 topics

Networking

1 topics

Storage

1 topics

Orchestration

2 topics

CI/CD

1 topics

Security

1 topics

Internals

1 topics

Production

1 topics

Linux

Fundamentals

3 topics

Processes

1 topics

Shell

2 topics

Networking

1 topics

Services

1 topics

Performance

1 topics

Automation

1 topics

Security

1 topics

Kubernetes

Fundamentals

1 topics

Workloads

1 topics

Networking

1 topics

Configuration

1 topics

Security

1 topics

Storage

1 topics

Scaling

1 topics

Observability

1 topics

Production

1 topics

CI/CD & GitHub Actions

Fundamentals

1 topics

GitHub Actions

3 topics

Security

1 topics

Deployment

1 topics

Testing

1 topics

Spring Boot

Core & Setup

14 topics

Configuration

5 topics

Web / REST

10 topics

Data Access

7 topics

Security

12 topics

Testing

5 topics

Actuator & Ops

4 topics

Advanced

4 topics

REST & Web

3 topics

Data & JPA

4 topics

Production & Advanced

6 topics

Microservices

Fundamentals

7 topics

Communication

7 topics

Discovery & Gateway

4 topics

Resilience

5 topics

Data Management

5 topics

Observability

4 topics

Security

4 topics

Deployment

5 topics

Patterns

6 topics

Apache Kafka

Fundamentals

11 topics

Producers

7 topics

Consumers

9 topics

Delivery Semantics

5 topics

Kafka Streams

8 topics

Kafka Connect

5 topics

Administration

8 topics

Spring Integration

3 topics

Advanced

8 topics

RabbitMQ

Fundamentals

6 topics

Exchanges

5 topics

Queues

6 topics

Reliability

3 topics

Dead-Lettering

4 topics

Advanced Queue Types

5 topics

Messaging Patterns

4 topics

Spring AMQP

4 topics

Operations

7 topics

Microservices

2 topics

MySQL

Fundamentals

5 topics

Joins & Set Ops

5 topics

Advanced Queries

7 topics

Indexes

6 topics

Query Optimisation

3 topics

Transactions

7 topics

Schema Design

4 topics

Scaling

4 topics

Administration

5 topics

Hibernate & JPA

Fundamentals

7 topics

Relationships

7 topics

Inheritance

4 topics

Querying

5 topics

Spring Data JPA

5 topics

Performance

7 topics

Transactions

5 topics

Advanced

7 topics

System Design

Fundamentals

7 topics

Data Management

7 topics

Communication Patterns

6 topics

Reliability & Fault Tolerance

7 topics

Architectural Patterns

7 topics

Storage & File Systems

5 topics

Real-World Designs

6 topics

Observability & Operations

5 topics

Operating Systems

Processes & Threads

12 topics

CPU Scheduling

8 topics

Memory Management

10 topics

Synchronization

6 topics

Deadlocks

6 topics

File Systems

4 topics

I/O & Kernel

4 topics

SQL

Schema & DDL

7 topics

DML & Querying

8 topics

Joins

8 topics

Aggregations

1 topics

Aggregation & Grouping

5 topics

Subqueries & CTEs

8 topics

Window Functions

7 topics

Indexing & Performance

6 topics

Low Level Design

Creational Patterns

8 topics

Structural Patterns

8 topics

Behavioral Patterns

10 topics

SOLID Principles in Practice

5 topics

LLD Interview Problems

15 topics

OOP & UML Fundamentals

4 topics

Computer Networks

Fundamentals

5 topics

Transport Layer

5 topics

Network Layer

5 topics

Application Layer

5 topics

Security

5 topics

Infrastructure

5 topics

Interview Patterns

5 topics

Java A–Z

Java Fundamentals

10 topics

OOP & Advanced Classes

18 topics

Collections Framework

10 topics

Streams & Functional Java

10 topics

Modern Java (9–21)

12 topics

I/O & Networking

6 topics

Design Patterns

10 topics

Concurrency & Threading

13 topics

JVM Internals & Memory

5 topics

Testing & Best Practices

6 topics

DSA

General

10 topics

DSA Patterns

Coding Patterns

13 topics

Interview Q&A

Career Roadmaps

Backend Engineer

5 topics

Java + React Full Stack

5 topics

Python + React Full Stack

5 topics

React + Next.js Full Stack

5 topics

AI Engineer

5 topics

Data Engineer

5 topics

Forward Deployed Engineer

5 topics

Data Analyst

5 topics

Data Scientist

5 topics

System Design Case Studies

Design a URL Shortener

5 topics

Design a Chat System

5 topics

Design a Social Media Feed (Twitter/X)

5 topics

Design a Video Streaming Platform (Netflix)

5 topics

Design an E-Commerce Platform (Amazon/Flipkart)

5 topics

Design a Ride-Sharing App (Uber/Ola)

5 topics

Design a Notification System

5 topics

Design a Distributed Cache

5 topics

Design a Rate Limiter

5 topics

Design a Video Streaming Platform

5 topics

Design Search Autocomplete

5 topics

Design Dropbox / Google Drive

5 topics

Design Ticketmaster / BookMyShow

5 topics

Design Instagram

5 topics

Formula Sheets

Quantitative Aptitude

14 topics