A enables your computer to connect to other computers or to the Internet?

Answer 1

To connect a computer to other computers (i.e. to a network) you need a network adapter, also called a Network Interface Card. This adapter should be suitable for a network which you want to connect to. Wireless adapters are for wireless networks, wired adapters are for wired networks.
A network connection.
if its file sharing a local network over your lan, or if its a game, social networking site on the internet its the internet.
A network card connnects to a router (wireless or LAN) the the router connects to other computers or a modem (intranet-telephone interface)

Answer 2

I would probably say that you mean an Internet Card, that is the piece of hardware that has a Ethernet port, or the wireless part. once you connect to the internet, you are going to have to connect all the other computers (that you want to network) to the internet as well. Then create a network that runs through you router.

Answer 3

The card that enables you to connect your computer to a network is called your Network Interface Controller (or network adapter). This may be a stand-alone card or in some cases an interface may be built into your motherboard. Most network adapters include a place where you can connect an Ethernet cable, and some may allow for wireless networking.

Answer 4

The internet does.