Short for Bearer-channel, the main data channel in an ISDN connection. Basic Rate ISDN (BRI) service consists of two 64 Kbps B-channels, and one D-channel for transmitting control information. Primary ISDN service consists of 23 B-channels (in the U.S.) or 30 B-channels (in Europe).
Compare with D-channel.
Short for bi-directional frame, or bi-directional predictive frame, a video compression method used by the MPEG standard. In a motion sequence, individual frames of pictures are grouped together (called a group of pictures, or GOP) and played back so that the viewer registers the video��s spatial motion. As the name suggests, B-frames rely on the […]
Most often used in databases and file systems, B-trees are tree structures (a type of data structure) that are optimized for situations when all or part of the tree must be maintained on a secondary storage device such as an optical disk or tape. A B-tree is designed to minimize the number of disk accesses.
- Bezier Curve
Pronounced bez-ee-ay, Bézier curves are curved lines (splines) defined by mathematical formulas. Nearly all draw programs support Bézier curves. Named after the French mathematician Pierre Bézier, Bézier curves employ at least three points to define a curve. The two endpoints of the curve are called anchor points. The other points, which define the shape of […]
- Baby AT
The form factor used by most PC motherboards prior to 1998. The original motherboard for the PC-AT measured 12″x13″. Baby AT motherboards are a little smaller, 8.5″x13″ usually. The Baby AT is being replaced by the new ATX form factor.
- Backspace key
A key that moves the cursor or insertion point backward one character space. In addition to moving the cursor backward, the Backspace key usually deletes the character to the left of the cursor or insertion point. It is particularly useful, therefore, for correcting typos. Note that PCs also have a Delete key, which deletes the […]