The grantor warrants that he or she is the lawful owner of the property, that there are no liens on the property, and that he or she will defend the grantee against any lawsuit brought as a result of problems with the title.
A Warranty Deed is generally used arm's length transactions where the grantor and grantee are not family members or friends.
The Warranty Deed is different from the Quitclaim Deed in that the latter does not make any warranties with regard to the title.