BeginnerAI
Prompt Engineering 101Cheatsheet
A beginner guide to prompt structure, system instructions, few-shot examples, and chain-of-thought techniques for LLMs.
Useful CheatsheetsPractical Life Skills Reference
Actionable cheat sheets for the skills that actually matter.
Direct and easy to read reference guides for modern life — build software and AI systems, grow personal wealth and navigate taxes, and optimize your everyday health and wellness.
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Recent cheatsheets
BeginnerMechanics
Engine Basics 101Cheatsheet
A clear primer on four-stroke internal combustion cycles, core engine anatomy, and basic maintenance checkpoints.
BeginnerMechanics
Fasteners and Hardware 101Cheatsheet
A quick reference on bolt grades, metric and imperial thread pitches, torque specifications, and locking mechanisms.
BeginnerMechanics
Electric Motors 101Cheatsheet
A primer on DC and AC electric motors, electromagnetic induction, torque curves, and motor control circuits.
AdvancedCode
JavaScript Currying and CompositionCheatsheet
Transform multi-argument functions into chained calls and combine small functions into pipelines.
AdvancedCode
JavaScript Event LoopCheatsheet
Learn how the call stack, microtask queue, and task queue control JavaScript execution order.
AdvancedCode
JavaScript GeneratorsCheatsheet
Learn how generator functions pause and resume execution to build lazy sequences and iterables.
IntermediateCode
JavaScript Optional ChainingCheatsheet
Access nested properties safely with optional chaining and pair it with nullish coalescing for defaults.
AdvancedCode
JavaScript Prototypal InheritanceCheatsheet
Understand the prototype chain, Object.create, and how class syntax wraps prototypal inheritance.
AdvancedCode
JavaScript Proxy and ReflectCheatsheet
Learn how Proxy traps and the Reflect API intercept and control object behavior in JavaScript.
AdvancedCode
JavaScript SymbolsCheatsheet
Use unique Symbol values as collision-free object keys and customize built-in object behavior.
IntermediateCode
JavaScript TimersCheatsheet
Schedule code execution using setTimeout and setInterval, and rate-limit handlers using debounce and throttle patterns.
IntermediateCode
JavaScript Type CoercionCheatsheet
Understand how JavaScript converts types automatically and avoid common equality and comparison bugs.
AdvancedCode
JavaScript WeakMap and WeakRefCheatsheet
Store object-keyed data and hold references without blocking garbage collection in JavaScript.
AdvancedCode
JavaScript Async IteratorsCheatsheet
Learn async iterators, async generators, and for await...of for consuming asynchronous data lazily.
AdvancedCode
JavaScript Call Apply BindCheatsheet
Control the this keyword explicitly using call, apply, and bind on any function.
IntermediateCode
JavaScript ClassesCheatsheet
Build objects with class syntax covering constructors, inheritance, static members, and private fields.
BeginnerAI
Claude API BasicsCheatsheet
A quick reference for making your first Claude API call, picking a model, and reading the response.
IntermediateAI
Claude API Tool UseCheatsheet
A quick reference for defining tools, running the agentic loop, and using the SDK tool runner with Claude.
IntermediateCode
JavaScript Fetch APICheatsheet
Master the Fetch API for making HTTP requests in JavaScript, including GET, POST, error handling, and working with JSON responses.
AdvancedCode
TypeScript Utility TypesCheatsheet
A practical reference for TypeScript's built-in utility types including Partial, Pick, Omit, Record, ReturnType, and how to compose custom utilities.
IntermediateCode
JavaScript ModulesCheatsheet
Organize JavaScript code with ES6 modules using named exports, default exports, and dynamic imports.
AdvancedCode
JavaScript Regular ExpressionsCheatsheet
Learn regex patterns, flags, exec, test, match, and replace for powerful string processing.
IntermediateCode
JavaScript Spread and RestCheatsheet
Use spread syntax to expand arrays and objects, and rest parameters to handle variable function arguments.
BeginnerCode
JavaScript StorageCheatsheet
Use localStorage and sessionStorage to persist data in the browser across sessions and refreshes.
BeginnerCode
JavaScript DestructuringCheatsheet
Master object and array destructuring for cleaner variable assignment and function parameters.
IntermediateCode
JavaScript Error HandlingCheatsheet
Handle errors gracefully in JavaScript using try/catch, custom error classes, and finally blocks.
IntermediateCode
JavaScript EventsCheatsheet
Handle browser events, event delegation, bubbling, capturing, and preventDefault with vanilla JavaScript.
AdvancedCode
Next.js Performance OptimizationCheatsheet
Profile apps, optimize bundle size, and implement advanced caching and streaming.
AdvancedCode
Next.js Streaming and Progressive RenderingCheatsheet
Stream content progressively with Suspense to improve perceived performance and UX.
AdvancedCode
React Component PatternsCheatsheet
Build scalable component architectures with established design patterns.
IntermediateCode
React Custom HooksCheatsheet
Build reusable custom hooks to extract component logic and share stateful behavior.