The most well-known example is probably of the Distorted Guitar, the kind of sound produced by heavy metal guitarists. That grungy, grating sound used in guitar solos is interesting, but I'm pretty sure that's not what a guitar actually sounds like. A twang on a guitar string produces a twang, not a Deep Purple power chord. That previous example also shows that Distortion and Noise are not always undesireable. They can be manipulated to good use.
Clipping is a form of distortion.
Clipping occurs when a sound signal's voltage increases past a point that the equipment cannot output. As such, instead of maintaining the real wave-form of a sound, the sound is abruptly truncated where equipment meets its limits. This can sometimes cause the grating-guitar sort of sound. To minimise noise and distortion when processing sound, transferring it from one component to another, or reproducing recorded sound, there is a standard type of audio signal called the Line-Level signal . This electronic representation of sound is similar to the types used to drive speakers or coming from microphones and guitars.