What are "Tags"?

[terracore]

So, after upgrading out VBulletin forum underneath each post there is this:

Tags
Separate tags using a comma.

You may add 25 tag(s) to this thread.

What is this and what does this mean? Am I totally forum retarded? lol

[Digital Jedi]

It's another way to make your threads searchable by using more relevant search terms defined by users. Then someone can either search for a term using the Tag Search in the drop down menu, or they can go to the Tag Cloud and browse the most common tags: http://www.cogonline.net/forums/tags.php

[Opserty]

Not really that useful as to explaining what they are but: http://www.vbulletin.com/forum/showthread.php?t=249460