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Web Design in a Nutshell, eMatter EditionGlossaryGlossary
μ-LAW
(Pronounced “myew-lah”) UNIX standard audio file format.
accessibility
Refers to making web pages available and readable to all users, including
those with disabilities such as sight or hearing impairments.
AIFF
Audio Interchange File Format. Standard audio format originally developed for
the Macintosh, which is now supported on PCs as well. It is one of the
formats commonly used for distributing audio on the Web.
alpha channel
In graphics, an extra channel for storing information about an image. The
alpha channel works like a mask that applies properties (such as transpar-
ency) to the pixels in the image. Other channels typically include color value
information—as in the red, green, and blue channels of an RGB image.
alpha-channel transparency
The method of transparency used by 24-bit PNGs, which uses an additional
(alpha) channel to store variable levels of transparency (up to 256) for each
pixel in the image.
animated gif
A GIF89a that contains multiple frames and a “control block” for controlling
the animation timing and display.
applet
A self-contained mini-executable program, such as one written in the Java
programming language.
ASCII files
Files that are comprised of alphanumeric characters. Some FTP programs refer
to ASCII files as “text” files.