computer network - A network is 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. One of the key features of a packet is that it contains the destination address in addition to the data.

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

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

Node - A node is 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.

IP address - short for Internet Protocol (IP) address. An IP addressis an identifier for a computer or device on a TCP/IP network. 

Bus Topology - Each node is daisy-chained (connected one right after the other) along the same backbone, similar to Christmas lights. Information sent from a node travels along the backbone until it reaches its destination node.

Ring Topology - 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. In a ring network, each node takes a turn sending and receiving information through the use of a token.

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. The token acts like a ticket, enabling its owner to send a message across the network.

Star Topology - 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-to-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.