A Packet Sniffer is a program that can record and filter network traffic on a machine or network switch.
Most of these programs (on Linux at least) use the pcap (Packet Capture) library.
Snort includes packet sniffing capabilities.
tcpdump(8) is a command line sniffer.
A pretty-yet-powerful packet sniffer is Ethereal, which uses a point-and-click GUI.
Part of CategoryNetworking. See also packet(7).
2 pages link to PacketSniffer: