Networking and Tagging Sites

A classic web 2.0 innovation, tagging sites allow people to add links to their favorite web sites, and to comment on or rate their favorite sites which were added by others. At it's best it allows a group to identify truly outstanding sites. At worst it allows link spammers to compromise the listings.

Networking sites allow users to create a profile for themselves, and link to other users profiles. You can build your contacts by finding users you don't know who are connected to users you do know.