Network - A group of computers connected together in a way that allows information to be exchanged between the computers.

Packet - A piece of a message transmitted over a packet-switching network.

Local area network (LAN) - Technologies that connect many devices that are relatively close to each other, usually in the same building.

Wide area network (WAN) - Technologies that connect a smaller number of devices that can be many kilometers apart.

Node - Anything that is connected to the network. While a node is typically a computer, it can also be something like a printer or CD-ROM tower.

Media Access Control (MAC) address - This is the physical address of any device -- such as the NIC in a computer -- on the network. The MAC address, which is made up of two equal parts, is 6 bytes long.

IP address - Internet Protocol (IP) address.

An identifier for a computer or device on a TCP/IP network. 

Bus - Each node is daisy-chained (connected one right after the other) along the same backbone, similar to Christmas lights.

Ring - Like a bus network, rings have the nodes daisy-chained. The difference is that the end of the network comes back around to the first node, creating a complete circuit.

Token - In networking, a token is a special series of bits that travels around a token-ring network. As the token circulates, computers attached to the network can capture it.

Star - In a star network, each node is connected to a central device called a hub. The hub takes a signal that comes from any node and passes it along to all the other nodes in the network.

Tree topology - A tree topology combines characteristics of linear bus and star topologies. It consists of groups of star-configured workstations connected to a linear bus backbone cable.

Protocol - An agreed-upon format for transmitting data between two devices. 

Peer-Peer Architecture - A type of network in which each workstation has equivalent capabilities and responsibilities.

Client-Server Architecture - A network architecture in which each computer or process on the network is either a client or a server.