How many I/O slots does a typical Motherboard has? and What are those?

Answer 1

Assuming you mean card slots, it depends on the size of the box. Anywhere from 3 to 6 is common.

They're used to put additional cards in the machine. For instance, if you wanted your machine to go on a wireless network but you didn't have wireless built into your machine, you could buy a wireless network card and put it in a slot. It's a way to add hardware capability.

Note that now most device add-ons are coming designed for USB instead, so it's not as necessary as it used to be to open up your machine and add a card in. Some high-speed functionality (such as graphics) usually will take a dedicated card, but many other things, from bluetooth to networking to art pads will plug into USB.