The Interactive Glossary: Defining the Net
Packet /
Packet Switching
Packet Switching

A packet is a chunk of information sent over a network. Packet-switching is the process by which a carrier breaks up data into these chunks or packets. Each packet contains the address of origin, the address of its destination, and information about how to reunite with other related packets. This process allows packets from many different locations to co-mingle on the same lines and be sorted and directed to different routes by special machines along the way.
E-mail messages and Internet telephone calls are broken into packets for transmission.