Pro Tools is a Digital Audio Workstation platform for Mac OS and Microsoft Windows operating systems, developed and manufactured by Digidesign, a division of Avid Technology. It is widely used by professionals throughout the audio industries for recording and editing in music production, film scoring, television and post production. Pro Tools has three types of systems; HD, LE, and M-powered. HD is the high-end package and is an integration of hardware and software. The hardware includes an external A/D converter and internal PCI or PCIe audio cards with onboard DSP.

Fundamentally, Pro Tools is similar to a multitrack tape recorder and mixer, with additional features that can only be performed in the digital medium. The high-end version supports sample rates of up to 192 kHz and bit depths of 16 and 24 bit, opens WAV, AIFF, mp3 and SDII audio files and QuickTime video files, and features time code, tempo maps, automation and surround sound capabilities.

In this you can watch Steve Vai demonstrated use pro tools in his studio

ProTools is a professional audio engineering software program made by Digidesign. Although it's used by top-notch pros in the radio industry, ProTools has a fairly easy learning curve, making it just as good for beginners.