Learn how to add subtitles in several languages to HTML video: track elements with kind subtitles, srclang and native-language labels, language codes, translation tips, right-to-left and Asian scripts, choosing a language with JavaScript, and common mistakes, with a live multi-language demo.
Learn the basics of international SEO with HTML: the lang attribute, hreflang alternate links, language and region codes, x-default, reciprocal links, URL structures, canonical links for each version, and good localisation habits. Includes an hreflang builder with sitemap output, a return-link matrix that finds missing links, and a live hreflang checker.