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These articles are static pages built from Markdown in the repository. They explain concepts and point to tools that run locally in your browser whenever the task allows.
MIME types and file extensions
How type/subtype MIME labels relate to dotted file extensions, why HTTP uses Content-Type instead of filenames, and when the same format has more than one valid label.
Published: 2026-06-26
Read article →Hex encoding: UTF-8 bytes explained
How hexadecimal represents raw bytes, why UTF-8 matters when you encode text as hex, and how hex dumps differ from URL percent-encoding and HTML numeric entities.
Published: 2026-06-26
Read article →UUID versions (and when v4 is enough)
How RFC 4122 UUIDs encode version and variant bits, what versions 1–5 mean in practice, and why random version 4 IDs are the right default for most applications.
Published: 2026-06-26
Read article →HTML entities: what to escape and why
How HTML character references work, which characters must be escaped in text and attributes, and why entity encoding is not the same as URL encoding or full XSS protection.
Published: 2026-06-05
Read article →URL encoding vs form encoding
How percent-encoding works in URLs, when encodeURI differs from encodeURIComponent, and why application/x-www-form-urlencoded treats spaces as plus signs.
Published: 2026-05-27
Read article →CSV to JSON — headers, types, and edge cases
How CSV maps to JSON objects and arrays, why types are ambiguous until you decide, and practical pitfalls like uneven rows, quotes, and BOMs—using browser-only tools on LocalTools.
Published: 2026-05-22
Read article →INI vs Java .properties — when to use which
How INI sections and Java .properties flat keys differ, where each format shows up in real projects, and how to convert between them and JSON locally in your browser.
Published: 2026-05-22
Read article →.env files: syntax, merging, and secrets hygiene
How dotenv-style files are parsed, what happens when keys repeat or files merge, and practical rules for keeping credentials out of the wrong places.
Published: 2026-05-17
Read article →What is JSONPath?
A practical introduction to JSONPath—how to point at nested JSON, filters, and recursive descent—with links to LocalTools’ browser-only evaluator and formatter.
Published: 2026-05-17
Read article →Minifying JSON safely
What JSON minification changes, what it preserves, and when to validate or format again—using browser-only tools on LocalTools.
Published: 2026-05-17
Read article →Generating TypeScript types from sample JSON
How tools infer interfaces from example payloads, what one sample cannot prove, and how to tighten types after generation—all in the browser on LocalTools.
Published: 2026-05-17
Read article →Validating and formatting XML in the browser
What browser-based XML checking really means, how parsing differs from schema validation, and what to expect when you pretty-print or minify—without sending files to a server.
Published: 2026-05-17
Read article →What is TOML?
A plain-language introduction to TOML for config and metadata, how it differs from JSON and YAML, and how to validate it locally in your browser.
Published: 2026-05-17
Read article →What is JSON?
A plain-language introduction to JSON for developers and data wranglers, with a link to LocalTools’ browser-only formatter.
Published: 2026-05-16
Read article →JSON vs YAML for config
When YAML shines for human-edited config, when JSON is the safer default, and how to convert between them locally in your browser.
Published: 2026-05-16
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