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9 concept guides for developers.
What Is JSON? Definition, Syntax & Examples
JSON (JavaScript Object Notation) explained: syntax rules, data types, examples, and common pitfalls for developers.
What Is a JWT? JSON Web Token Explained
Learn what JWT (JSON Web Token) is, how it works, its structure (header.payload.signature), and common use cases in authentication.
What Is Base64 Encoding? Explained for Developers
Base64 encoding explained: how it works, why it's used, URL-safe variants, and when to encode/decode data.
What Is a UUID? Universally Unique Identifier Guide
UUID explained: versions (v1, v4, v7), format, collision probability, and when to use UUIDs in software.
What Is a Cron Expression? Cron Syntax Explained
Cron expressions explained: field meanings, syntax, examples, and how to schedule jobs with crontab.
What Is a Regular Expression (Regex)?
Regular expressions explained: syntax basics, common patterns, flags, and practical examples for developers.
What Is a Unix Timestamp? Epoch Time Explained
Unix timestamp (epoch time) explained: seconds vs milliseconds, conversion, timezone considerations, and the Year 2038 problem.
What Is Markdown? Syntax & GitHub Flavored Markdown
Markdown explained: basic syntax, GitHub Flavored Markdown (GFM) extensions, and when to use Markdown vs HTML.
What Is cURL? Command-Line HTTP Tool Explained
cURL explained: syntax, common flags (-X, -H, -d), copying from DevTools, and converting cURL to code in any language.