HTML

See also CSS.

Tools to use for Writing

• Expounder: for providing in-line explanations that are revealed on clicking.
• A blog post on using “Text Fragments”: for linking to any arbitrary part of a web page based on specific text

Tips and tricks for web design

• Web developer's guide to AVIF images
• Web design in 4 minutes

Learning HTML

• HTML for people
• HTML editor with realtime preview, found via this comment on Hacker News