How does TV card work?

Not such an easy answer, but I will take a shot. Basically a tv card is a pci slotted card fitted with a tv tuner. The idea is so that you can watch TV on your PC. The card itself will not split the coax cable coming from the wall, you will need to get a Y splitter (Radio Shack, WalMart) and some lengths of coax. The coax can come with the end already attached or you can buy the coax cable, cut it to lenght, and fit the end yourself. The Y splitter will have 1-In and 2-Out ports, the 1-In is from the wall, and 1 of the 2-Outs would go your TV and the other to the back of your PC and the tuner card. With this set up, yes, you can watch two different channels between the TV and your PC.

Now, keep in mind that just getting the tuner card and associated hardware is one thing, but having the software and applications to watch TV, PVR, and Time Shift is something different. Probably the best bet is to get a TV Tuner software combo package. Something like the Beyond TV from Snapstream would be an excellent choice as the software is robust and top notch and they also sell a software and tv tuner package for $99. The firefly remote is worth the price itself.

Good luck!