Dreamweaver is a web authoring program that allows users to create and edit websites using a WYSIWYG interface. It generates HTML code behind the scenes as the user works. Dreamweaver supports features like CSS, JavaScript, templates, and publishing websites to servers. The document provides basic instructions for starting Dreamweaver, creating a new site, adding pages, entering and formatting content like text, lists, and images. Formatting options include fonts, sizes, colors, and alignments that can be applied with controls in the Properties inspector.