to see what we see on our computer on the tv screen do we just need the cable with the 3 colored prongs to go in the tv skar plug or do we need some software ?
You need a converter card/software setup. The software sends the info to the converter card installed on your PC. from the converter card, you have your regular cabels (red, yellow, white) going to the TV. Go to a place like Best Buy and tell them you need a TV/PC converter kit. Also allows you to watch TV on laptop.