A really great one-page guide to HTML from Bruce. I like his performance-focused intro:
If your site is based on good HTML, it will load fast. Browsers incrementally render HTML—that is, they will display a partially downloaded web page to the user while the browser awaits the remaining files from the server.
Modern fashionable development techniques, such as React, require a lot of JavaScript to be sent to the user. When it’s all downloaded, the user’s device must parse and execute the JavaScript before it can even start to construct the page. On a slow network, or on a cheaper, low-powered device, this can result in an excruciatingly slow load and is a heavy drain on the battery.