HTML is a markup language for the web. It's used to designate elements in documents, such as paragraphs and links, so that they can be rendered by programs such as browsers. HTML stands for Hypertext Markup Language.
CSS is a language for describing style in markup languages, usually HTML. CSS is essentially a set of rules that can then be applied when rendering a HTML document. CSS stands for Cascading Style Sheets, which refers to the fact that there is an order of precedence in how CSS rules are applied to a document.
Opening Activity
Basic template
Tags and elements
Paragraphs and headings
Links
Images
Linking to a stylesheet