
What is CORS and Why is My JavaScript fetch Blocked?
CORS explained for JavaScript fetch errors, including same‑origin policy, server opt‑in, preflight requests, credentials, and what front‑end code can fix.
Articles
JavaScript is the working language behind most of my front‑end writing, from small browser behaviours to application state and asynchronous code. These articles favour the mechanism behind a feature over a clever trick, whether the subject is callbacks, async code, or a language edge that only becomes obvious in production.

fetch Blocked?CORS explained for JavaScript fetch errors, including same‑origin policy, server opt‑in, preflight requests, credentials, and what front‑end code can fix.

Create and dispatch custom events in JavaScript with CustomEvent, detail payloads, bubbling, naming choices, cancellation, and component examples.

HTML fundamentals explained through semantic structure, browser parsing, accessibility, and how markup choices affect modern front‑end work in practice.

Object.freeze(), Object.seal(), and preventExtensions()Object.freeze(), Object.seal(), and preventExtensions() explained clearly, including what each allows, what they block, and why shallow locking matters.

Number.isNaN(), Number.isFinite(), and Number.isInteger() in JavaScriptNumber.isNaN(), Number.isFinite(), and Number.isInteger() explained through strict numeric checks, coercion traps, parsing boundaries, and validation.

Browser and Node.js JavaScript compared through host APIs, globals, modules, async behaviour, DOM access, server APIs, and environment mix‑ups cleanly.

Promises make asynchronous JavaScript easier to reason about. This introduction covers pending, fulfilled, rejected, and how chaining cleans things up.

Function declarations vs. function expressions vs. arrow functions in JavaScript, including hoisting, this, readability, and when each style fits best.

Rest and spread operators solve different problems in JavaScript. This beginner‑friendly guide shows the syntax, the difference, and common use cases.

Use JavaScript template literals for multi‑line strings, interpolation, cleaner formatting, practical string construction, and pitfalls around whitespace.

String.startsWith(), endsWith(), and includes() in JavaScriptUse startsWith(), endsWith(), and includes() in JavaScript for clearer string checks, case‑sensitive matching, position arguments, and readable intent.

window.resize Events in iOSUnderstand phantom window.resize events in iOS Safari, including dynamic browser UI, viewport changes, orientation, user interaction, and mitigation patterns.

for...in vs. for...of in JavaScriptCompare for...in and for...of in JavaScript, including keys, values, arrays, objects, iterables, inherited properties, and choosing the clearest loop.

JSON.parse() and JSON.stringify() Explained for BeginnersJSON.parse() and JSON.stringify() explained clearly, including when to convert data, common mistakes, localStorage use, and why functions disappear.

Default parameters in JavaScript explored in more depth, including expression defaults, evaluation order, undefined, API design, and subtle edge cases.

Understand live HTMLCollection views, static NodeList snapshots, mutation‑skipping bugs, Array.from() conversion, and safe DOM iteration in 2016.

Array.from() and Array.of() in JavaScriptArray.from() and Array.of() in JavaScript explained with NodeLists, array‑like objects, generated arrays, and why new Array() can still catch people out.

Default parameters in JavaScript explained from the ES6 syntax through undefined handling, old workarounds, cleaner calls, everyday use, and function design.