Y

Y-Axis (computer)
Vertical, perpendicular to the X axis, in a two-dimensional system of coordinates.

Y-Delta Transformations (computer/microelectronics)
Electrically equivalent circuit networks with three terminals, one connected internally by a Y configuration; the other being connected internally by a delta configuration. If a circuit connects three terminals with one another, it is called a three-terminal network.

YC (A/V, computer)
Encoding method used in S-Video. In YC, the luminance (Y) and chrominance (C) signals are separated. The chrominance signal incorporates both hue and saturation information. The Y/C inputs are the luminance (brightness) and the chrominance (color) plugs on a camcorder, or the receptacles on the back of a VCR or TV (see S-VHS).

Ymodem (communications, computer)
Asynchronous communications protocol for personal computers that is identical to the Xmodem CRC protocol, with the addition of batch file transfer.

YUV (A/V, computer)
Encoding method used for digital video applications. For this method, Y represents the luminance of the image, and U and V define the hue and saturation. When YUV signals are compressed, the compression ratio is indicated for each element. In the ratio 4:2:2, the luminance signal is compressed by a factor of 4, and the hue and saturation signals are compressed by a factor of 2. YUV encoding is used in IBM's M-Motion MMP files.