Subdomain or Subfolder?

[AndrewC]

Off the two what do you guys think should I install a forum on and which is better from the SEO point of view as well?

"www.mysite.com/forum"

or

"www.forum.mysite.com"

[Peter]

I think you are better off using a subfolder "www.mysite.com/forum" rather than a subdomain. The SEs consider a subdomain as a separate domain and you will have to start everything afresh including link building for the subdomain. Advantages of a sub folder as I understand are: link popularity and page rank flow from the main domain to the sub folder.

[Alexis]

A subfolder would be better than a subdomain as a subdomain is considered a separate domain by the SEs so from the SEO point of view the rankings and PR of the main domain won't help the subdomain. You will need to start from scratch to build the PR and get the subdomain a good ranking.