// reference
Developer reference
Cheat sheets and lookups for the details you always half-remember — regex syntax, HTTP headers and MIME types. Each one links straight to the tool that puts it to work.
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Cron Syntax How cron expressions work — the five fields, special characters, @macros and ready-to-use schedule examples. HTML Entities Common HTML entities — reserved characters, symbols, currency, punctuation and arrows — with their named and numeric codes. HTTP Headers Reference The HTTP request, response, caching, CORS and security headers you meet every day — what each one means, with a real-world example. HTTP Status Codes Every common HTTP status code from 1xx to 5xx, with its name and what it means — grouped by category. MIME Types Reference Common MIME (media) types by category — text, application, image, audio, video and fonts — with the file extension each maps to. Regex Cheat Sheet A quick reference for JavaScript regular expressions — character classes, quantifiers, anchors, groups, lookaround, flags and ready-to-use patterns.
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