Richard Byrne posted this article on his blog. This is a great explanation of each type of web document. There are some great examples at the bottom of the chart (Google Spreadsheet). Here is a direct link to the chart:
Link: Free Technology for Teachers: 140 New Things Being Tried In Classrooms This Fall Richard Byrne asked his readers (http://www.freetech4teachers.com/) to submit new things they were trying in their classroom this year. In 72 hours there were 140 genuine responses.