1. The computer needs a cat (modem) to connect the computer with a telephone line, dial-up or broadband Internet access.

2. To connect two or more computers, you need to connect the cat and the router with a network cable separate from the cat, and then connect the computers with a network cable separate from the router.

1. To connect the local area network, the network cable is essential. There are three kinds of common network cables in LAN: twisted pair, coaxial cable and optical cable.

2.？ Twisted pair is a data transmission line composed of many pairs of wires. It is characterized by its low price, so it is widely used, such as our common telephone line. It is used to connect RJ45 crystal head. There are two kinds of them: STP and UTP, and UTP is commonly used.