In forum posting a thread is made by some one. Which may be a query or a news or some important discussion. In which other people who have the solution or who want to perform some participation in discussion may take part.
Major search engines loves forums. The cause is in forum there is always a fresh content and above all it is made to help people. These forums have a new content every second. So it is a source of fresh information.
In forum posting people can post the link or the source of there knowledge. These are taken as a back link by all major search engines. But it is a bad place for spamming. Many people try to spam but they end up with permanent ban by the forum admin. So be careful when doing forum posting that it not get spammed.
