HTML was initially intended as, and still largely is, a markup language. An HTML file provides a container and presentation for other types of content. If you s

HTML was initially intended as, and still largely is, a markup language. An HTML file provides a container and presentation for other types of content. If you saved all those types of content into the same file you'd have many of the problems HTML was specifically designed to avoid, like bloat, vendor lock-in, format incompatibility, and editing difficulty.