Monday, August 27, 2001		Bits & Bytes

Daemon: Pronounced demon or damon, a process that runs in the background and performs a specified operation at predefined times or in response to certain events. The term daemon is a UNIX term, though many other operating systems provide support for daemons, though they're sometimes called other names. Windows, for example, refers to daemons and System Agents and services.

TPI: Short for tracks per inch, the density of tracks on a disk. For example, double-density 5.25-inch floppies have a TPI of 48, while high-density floppies record 96 TPI. High-density 3.5-inch diskettes are formatted with 135 TPI. Hard disks have TPIs in the thousands.

Superparamagnetism: In magnetic disk drive storage technology, the fluctuation of magnetization due to thermal agitation. When the areal density — the number of bits that can be stored on a square inch of disk media — of a disk medium reaches 150 gigabits per square inch, the magnetic energy holding the bits in place on the medium becomes equal to the ambient thermal energy within the disk drive itself. When this happens, the bits are no longer held in a reliable state and can "flip," scrambling the data that was previously recorded.