Firmata: a generic communicating protocol between microcontrollers and host computer
Firmata is a generic protocol for communicating with microcontrollers from software on a host computer. It is intended to work with any host computer software package. Right now there is a matching object in a number of languages. It is easy to add objects for other software to use this protocol. Basically, this firmware establishes a protocol for talking to the Arduino from the host software. The aim is to allow people to completely control the Arduino from software on the host computer.
Remark: Currently Firmata library not included in Arduino IDE 1.5.1 yet ...