Audio-Visual Equipment Pictograms are a set of shapes used by companies such as Sony, Panasonic, Aiwa, Technics, and other makers of audio and video electronics. They are usually seen on buttons for such operations as play, stop, pause, etc., on the device itself or on a remote control.
The pictograms seem to be standard throughout the industry, and show elegance and simplicity in their design. They have a meaning even to those unfamiliar with them.
Play - Usually denoted by a single triangle that points to the right. Interpretation: The triangle is like an arrowhead, and arrows indicate a direction. The single triangle implies "move forward", which is what the play button does.
Stop - A square. Interpretation: The square represents immobility, or mass. In stop mode, nothing moves.
Fast Forward / Rewind - Two equilateral triangles pointing right in the case of Fast Forward, left for Rewind. Interpretation: these buttons define direction. The right always implies going forward, the natural direction, while left goes in reverse. Since ffwd and rewind move faster than play, there are two triangles.
Skip Forwards / Backwards - Similar to fast forward, there are two triangles, but they always point towards a vertical line. Interpretation: We want to move at a fast speed (hence, two triangles), but we wish to stop at a logical point. This point is represented by the vertical line, an absolute location.
Pause - Represented by two tall rectangles. Can also be thought of as a square with a rectangle cut from its centre. Interpretation: Like stop, we imply immobility, but the piece missing in the square implies a meaning in the immobility, that the current position is remembered, and playing can begin anew.
Record - A circle. Interpretation: The circle implies an open eye, because the equipment is "seeing" and recording input.