Web+Pages

Static Pages
At one time static web sites were the only kind you could make. These pages can have all kinds of content, but visitors cannot interact with the page.

[|Google Pages] - http://pages.google.com/ (A late arrival, but like most Google products it's easy to use.) [|Tripod] - http://www.tripod.lycos.com/ (One of the first to provide free web site hosting, they now also support blogging. Now owned by Lycos.) [|HotChalk] - http://www.hotchalk.com/ (An easy way for teachers to create their own web sites.)

Wikis
A wiki is in many ways like a static page, but instead of one person being able to edit the page a large group of people can make additions/corrections. This is a scary concept for many people, but every change is saved just in case. If a vandal happened to put inaccurate or inflammatory information on this page, for example, anyone could "roll it back" to a previous version.

[|PB Wiki] - http://pbwiki.com/ ("It's as easy to make as a peanut butter sandwich." - Hence the name.) [|Wikihost.org] - http://wikihost.org/ (I've never used this one.) [|Wikispaces.com] - http://wikispaces.com/ (Easy to use. If you tell them you're using them for K-12 education they take the ads off your page.)

Blogs
I could go on for a whole presentation about blogs, and as a matter of fact I did! You can see my Edublogging 101 wiki here.