Javascript terms

3 terms of 1444 total

⚡ From DOM manipulation to async superpowers

JavaScript has evolved from a scripting curiosity into a full-stack language powering browsers, servers, and everything in between. This category covers the language core — closures, prototypes, async patterns, the event loop, modern ES2024+ features — as well as runtime behaviour that trips up developers at every experience level. Understanding JavaScript deeply means fewer bugs and more confident code.

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undefined vs null — Subtle Differences ES5

undefined means 'not yet assigned' (declared but empty); null means 'intentionally absent' — they're different values but both falsy, and typeof null === 'object' is a famous JS bug.

2mo ago javascript beginner

Unhandled Promise Rejection ES2015

An unhandled Promise rejection occurs when a rejected Promise has no .catch() or try/catch handler — Node.js 15+ terminates the process on unhandled rejection by default.

2mo ago javascript intermediate

URL & URLSearchParams API ES2015

URL and URLSearchParams provide structured URL parsing and query string building — the JavaScript equivalent of PHP's parse_url and http_build_query.

2mo ago javascript beginner