pre amp

I am very new to this field but ultimitalty want to design my own 3 way floor standing speakers, but dont really know where to start.
My first question is 'what is a pre amp?' is it designed so i can have 2 amps running speakers, i currently have 2 amps and want to run my speakers from the second amp which is near my computer, can i output from this amp to the amp hooked up to the speakers on the other side of the room, or will it damage it?