4 analog in (1 Mic TRS with included adapter to XLR, 1 instrument 1/4", 2 more inputs on either 2 TRS or 1 mini stereo 1/8"), 4 analog out (2 TRS, 1 stereo mini 1/8"), S/PDIF out, headphone out (1/8"). Zero-latency monitoring. Comes with AudioDesk software (Digital Performer w/o MIDI). Might be USB 1.