The inquisition was a court designed to combat what?

The inquisition was set up by the Roman Catholic church, to suppress heresy. In this context, heresy means any acts or dogmas opposing those of the Roman Catholic church. The inquisition was, so to speak, the religious police and besides that an instrument to keep the church pure (orthodox), an instrument of power.

You will find some very good articles on Inquisition at answers.com (for instance by using 1-click answers). The Inquisition is designed to do evil in the name of good. Using it the Church murdered the innocent and enriched itself (or its officers, more properly) with the property it confiscated from them and their families. There is no morally relative argument that can justify the bloody destruction it wrought upon Europe and America, and indeed, in Christian terms, such moral perversity as the Inquisition can only be the product of Satanic influence.