ProTracker is THE tracker of the Amiga and the successor to SoundTracker/NoiseTracker. Developed by Lars 'Zansen' Hamre, Anders 'Photon' Bjerregaard and others, ProTracker appeared in 1990 as freeware. It uses the 4 hardware channels of the Paula chip for MOD files in Amiga MOD format. Features: 31 samples, 64 patterns, effect commands (portamento, arpeggio, volume slide etc.), sample editor. ProTracker 2.3d is the most used version. The MOD format became the standard for tracker music worldwide and influenced FastTracker, Impulse Tracker and all modern trackers.