Quagga is a fork of the Zebra routing daemon. Quagga originally consisted of the -pj patchset to Zebra, and was created because of a difference in beliefs between the Quagga developers (Faster development == more features, and faster bug finding and fixing) and the Zebra developers (Stable development).

A lot of people tend to use Quagga these days when they need a Linux machine to participate in a routing network. Quagga's growth in the last year or so has been huge, seeing development of many new features as well as a lot of code cleanups.

A Quagga is a now extinct creature that is closely related to a Zebra.