When you enable full text search within InstantForum you can choose from two difference search types. These are explained further below.
Within InstantForum the only difference between the ContainsTable & FreeTextTable search options is the use of inflection. The FreeTextTable option has inflection enabled by default whilst the ContainsTable option does not have inflection enabled.
Inflection allows SQL server to find all nouns & verbs of words you search for using an internal thesaurus within SQL Server.
For example with FreeTextTable enabled if you search for "drove" results with the terms driving, driver, driven, drive etc will be returned. Whilst if you have ContaisTable enable only results with the original search term of "drove" would be returned.
Because of this inflection FreeTextTable is more expensive than ContainsTable however FreeTextTable can returned a broader set of search results for users to browse through due to the use of inflection.