Pro Tools is a nonlinear recording editing system that lets you rearrange and mix recorded material nondestructively. Nonlinear editing simply means that you can cut, copy, paste, move, delete, trim, and otherwise rearrange any audio, MIDI, or video in the Pro Tools Edit window.
Nonlinear editing provides significant advantages over dubbing (re-recording), and cutting and splicing magnetic tape. It gives you the greatest possible flexibility for editing and arranging, and it is all nondestructive and “undoable.” Additionally, with nonlinear editing in Pro Tools, you will never introduce any degradation of audio fidelity as you would with tape.