MAVLink
From Dronepedia
An LGPL-licensed serial data transmission protocol produced for the pixhawk project, developed by Lorenz Meier and the PixHawk team at ETH-Zurich. Allows for control of up to 255 aircraft on a single channel, operation on numerous microcontrollers, and data correction. Used in the qGroundControl groundstation, and part of the Pixhawk communication stack, along with MAVMesh, a mesh network.
MAVLink is built on MIT's lcm, a real-time messaging framework.
MAVLink is implemented as a capability on some other autopilots as well, such as the Ardupilot Mega.
