The packet is a term first coined by Donald Davies in 1965 that is used to describe a segment of data sent from one computer or device to another over a network. You can think of it as a package filled with data being delivered to another area. A packet is used because it divides data into easier-to-manage "chunks," which move information more efficiently and keep network resources from being tied up by a single, larger file.
What is in a packet?
A packet contains a source, destination, data, size, and other useful information that helps packet make it to the appropriate location and get reassembled properly. Below is a breakdown of a TCP packet.
Network packet basics
- Another name for a packet is a datagram.
- Data transferred over the Internet is sent as one or more packets. The most common packet sent is the TCP packet.
- The size of a packet is limited, so most data sent over a network is broken up into multiple packets before being sent out and then put back together when received.
- When a packet is transmitted over a network, network routers and switches examine the packet and its source to help direct it to the correct location.
- During its transmission, network packets can be dropped. If a packet is not received or an error occurs, it is sent again.