What do you need to write HTML?

Any plain text editor. Windows Notepad will do, but there are many text editors specifically geared toward writing HTML, which can save you a lot of typing.

Go to your favourite search engine and search for "html editor"; you will get LOTS of matches

Whatever you use, the HTML must be saved as plain text, and the document must have the extension .htm or .html.

HTML Editors - a very short list (all but Dreamweaver are FREE): KompoZer (WYSIWYG)*, Komodo, NotePad++, 1st Page, EditPad, Bluefish, Dreamweaver (WYSIWYG)*

* WYSIWYG = What You See Is What You Get = it's much like using a word processor.

The World Wide Web Consortium has a page of browsers and authoring tools.

What do I need to view HTML?

Any web browser. A web browser is just a program (software) specifically made for viewing web pages. Examples of web browsers are Microsoft's Internet Explorer (not recommended because of security problems), Firefox, Opera, Safari, and, well, there are lots of them. Most are free.