pyoui is a console Python program that lets you know which vendor has made an Ethernet/Bluetooth device. OUI stands for Organizationally Unique Identifier. In every electronic device that has a MAC address, the first (most weighted) 24 bits are the OUI, and they identify the vendor of that device. When you are sniffing network traffic, you may be interested in which network cards are active, or even if a MAC address is faked. This program is intended to help you with such things.