No matter if you use server-side or client-side scripting you need to use html for user output. When html was created the idea was to develop a language that could show information and documents and nothing else. In the early 90's, when usage of the web boomed people wanted to view pages with a more dynamic content. That is why scripting languages is used together with html - the scripting language provides the static content and interactivity with the user while html is used for user output.

The html-file is divided into two parts, the hidden head that contains information about the rest of the file and the body that contains what the visitor viewing.