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Original technical guides written for the tools on this site.
Base64 Encoding Explained: How It Works and When to Use ItA practical guide to Base64: the 64-character alphabet, padding, URL-safe variants, size overhead and common developer use cases.Unix Timestamps Explained: Epoch, Seconds vs MillisecondsWhat Unix time is, why it ignores leap seconds, how to tell seconds from milliseconds, and timezone pitfalls when converting.MD5 vs SHA-1 vs SHA-256: Choosing a Hash FunctionDigest sizes, collision resistance, speed, and which algorithms are safe for integrity checks versus passwords and signatures.UUIDs Explained: v4 vs v7 vs ULID for Database KeysHow UUIDs are structured, why random v4 keys fragment B-trees, and when time-ordered v7 or ULID are the better primary key.URL Encoding Rules: Reserved Characters and Percent-EncodingWhich characters must be percent-encoded, the difference between encodeURIComponent and full-URL encoding, and query vs path rules.JSON vs YAML vs TOML: Configuration Formats ComparedSyntax differences, comments, data types, tooling and which format fits APIs, Kubernetes manifests and app config files.CIDR and Subnet Masks Explained with Worked ExamplesHow prefix lengths map to masks, how to compute network, broadcast and usable host ranges, and common sizing mistakes.JWT Anatomy: Header, Payload, Signature — and Why Decoding Is Not VerifyingThe three Base64url segments of a JSON Web Token, standard claims, signature algorithms, and safe debugging practice.