Who is the woman dressed in purple and scarlet in Revelation 17 supposed to be?

I have heard this to be the Roman Catholic church. As I am not ready to rule that out, I have heard other meanings. One was the Seat of Satan. The premise of this is likened to the description of the strange woman in proverbs. It is the system that Satan uses to control and deceive the masses. Either of the two could be correct because the RCC has spread it's influence to the entire world.