DevGuides
The formats and protocols behind the tools, explained with real examples. Each guide links to the tool it belongs to, so you can read and then try.
How to Validate JSON and Fix the Most Common JSON Errors
Trailing commas, single quotes, unquoted keys, stray comments, truncated payloads: the twelve JSON mistakes that cause almost every parse error, how to spot each one, and a workflow that finds them in seconds.
2026-10-23Public vs Private IP Addresses: What's the Difference?
Your devices live behind one public address with private addresses of their own. How NAT makes that work, the private ranges and their special cases, and how to find each address when you need it.
2026-10-23Regular Expressions Cheat Sheet: Patterns You'll Actually Use
A compact regex reference plus the ten patterns worth memorising — email, URL, dates, IPv4, hex colours, slugs, UUIDs — each one explained piece by piece, with the traps called out.
2026-10-23How DNS Works: From a Domain Name to an IP Address
The lookup chain behind every URL: recursive resolvers, root and TLD servers, authoritative answers, TTLs and caching — plus the record types you'll actually meet and the failures they explain.
2026-10-23UTC vs GMT vs Local Time: A Developer's Guide
UTC is a standard, GMT is a time zone, and local time is a presentation choice. What each term really means, why they usually read the same, and the rules that keep time bugs out of your systems.
2026-10-23JSON to CSV: How to Convert, and When Each Format Wins
JSON is a tree and CSV is a grid — converting between them means making decisions about nesting, types and quoting. How the conversion works, the rules that keep it lossless, and how to choose.
2026-10-23URL Encoding Explained: A Percent-Encoding Reference
Why URLs need percent-encoding, the difference between encoding a component and a whole URL, a reference table for the characters that matter, and the + vs %20 question settled.
2026-10-23CIDR Notation and Subnetting for Beginners
What 192.168.1.0/24 really means: network bits, host bits, netmasks, usable ranges, and how to split one network into smaller subnets — with worked examples.
2026-10-22What Is a JWT? JSON Web Tokens Explained
A JSON Web Token is three Base64URL segments and a signature. How JWTs are structured, how the claims work, how verification really happens, and the mistakes that make them insecure.
2026-10-22JSON vs YAML: Key Differences and When to Use Each
JSON and YAML carry the same data but behave very differently: syntax, types, comments, failure modes and tooling, plus a practical rule for choosing between them.
2026-10-22Unix Timestamps Explained: Epoch Time, Milliseconds and Time Zones
What a Unix timestamp counts, why seconds and milliseconds keep getting mixed up, what happens in 2038, and how time zones, UTC and GMT fit in — with examples.
2026-10-22Base64 Encoding Explained: Why It Exists and How It Works
Base64 turns binary data into safe text at a 33% size cost. Why the internet needed it, how the 3-bytes-to-4-characters trick works, the variants, and the mistakes to avoid.