Notes on code, craft & the tiny decisions that ship better software.

What is ECMAScript and how is it different from JavaScript? Learn the history of ES1, ES2, ES3, ES5, ES6, ES2016–ES2026 and the major features introduced in each version.

Learn JavaScript closures from scratch with simple examples. Understand lexical scope, how closures work, data privacy, callbacks, setTimeout, and common interview questions.

Learn the differences between Map, Set, WeakMap, and WeakSet in JavaScript. Understand their syntax, use cases, key differences, memory behavior, and when to use each.

What exactly happens when JavaScript accesses a variable before its declaration? Learn how hoisting works with `var`, `let`, and `const`, including the Memory Creation Phase and Temporal Dead Zone with practical examples.

Confused about JavaScript Scope? Learn the differences between Global Scope, Function Scope, Block Scope, and Lexical Scope with simple examples, interview tips, and best practices.

Confused about whether to use a `Map` or an `Object` in JavaScript? This guide compares their performance, iteration, key handling, and real-world use cases to help you make the right choice.

Learn JavaScript Promises from the ground up. This guide explains how Promises work, why they were introduced, promise states, chaining, error handling, and real-world examples to help you write better asynchronous JavaScript.

Learn how JavaScript Execution Context works behind the scenes. Understand the Global Execution Context, Function Execution Context, Creation Phase, Execution Phase, Hoisting, and the Call Stack with practical examples.

Master the JavaScript Event Loop with easy-to-understand examples. Learn about the Call Stack, Web APIs, Callback Queue, Microtask Queue, Promises, async/await, and interview questions.