When a record is played faster on a turntable it also sounds higher; time-stretching breaks that link. Software analyses the audio and rebuilds it from tiny grains or segments, so a loop recorded at 92 BPM can be fitted to a 78 BPM beat while staying in the same key. Ableton Live calls this warping and offers several modes, tuned for drums, single melodic lines, textures and full mixes, because no single method suits every sound.
Stretch audio far enough and artefacts appear, such as clicks, smeared attacks or a grainy, fluttering tone. Many jazz lo-fi producers treat these side effects as colour, slowing a sampled phrase until it turns hazy. The alternative, changing speed and pitch together as a turntable does, remains popular for its record-like character; Live calls that mode Re-Pitch.