HTML Cheat Sheets
https://htmlcheatsheet.com
https://digital.com/tools/html-cheatsheet/
Download a visual cheat sheet

Bad HTML – things to avoid
https://badhtml.com

Great free tutorial website
https://marksheet.io/

W3 Schools
How tos
Examples

Colour Codes
RGB Colour Codes
Colour schemes for websites

Further Reading…

HTML & CSS by Jon Duckett