Audio Systems: laptop dji-ing, fellow dj, virtual turntable

Question
I am considering going to laptop djing..using pc dj software..I have spoken provisonally to a fellow dj and I need clarification on something plz if you are able too.he mentioned a sound card which is explanatory in itself.I wanted to run the laptop on a spare channel on my mixer..which is a numark three channel mixer..but my fellow dj mentioned a midi controller..do I really need a midi controller or is my own mixer ok to use to give me what I need....many thanks

Answer
You don't need the midi controller if you are queuing from your computer using your mouse and hot keys. As an ex pro DJ myself your DJ friend has a good point. A midi controller lets you work old school as I did in the 70's. It lets you use a virtual turntable and CD player to queue, scratch, sync, overlay effects, etc. It's really a question of how pro do you want to be?