HTML Entities: A Quick Reference and How They Work
By qc_admin
HTML entities are text codes that stand in for reserved or awkward characters. What they are, when you must use them, and a reference of the common ones.
Category: Web Development
HEX, RGB and HSL Colour, Explained
By qc_admin
How HEX, RGB and HSL describe the same colours in different notations, how to convert between them, and why HSL is easier to reason about by hand.
Escaping Strings in JSON, HTML, and URLs
By qc_admin
Each context has its own escaping rules, and mixing them causes bugs and security holes. How JSON, HTML, and URL escaping differ, with worked examples.
CSS Viewport Units: vw, vh, vmin, vmax
By qc_admin
What vw, vh, vmin and vmax measure, why 100vh caused mobile scrolling bugs, and how svh, lvh and dvh fix the moving-browser-bar problem.
UUID v4 vs v7: What Changed and Why
By qc_admin
How UUIDs are structured, why v4 is fully random, how v7 embeds a millisecond timestamp for index locality, and the privacy tradeoff of a time-ordered ID.
URL Encoding: When It’s Needed and When It Breaks
By qc_admin
How percent-encoding works, reserved vs unreserved characters, encodeURIComponent vs encodeURI, %20 vs +, and the double-encoding bugs that break URLs.
Reading a Diff Properly
By qc_admin
How to read a unified diff: the @@ hunk header, + and – lines, context lines, line-level vs word-level diffs, and when to ignore whitespace.
Content Security Policy for People Who Keep Breaking It
By qc_admin
A plain explanation of CSP: default-src, script-src, connect-src, self and unsafe-inline, why inline scripts break, and how connect-src blocks data exfiltration.