The New Hacker's Dictionary

wheel // n.

[from slang 'big wheel' for a powerful person] A person who has an active wheel bit. "We need to find a wheel to unwedge the hung tape drives." (See wedged, sense 1.) The traditional name of security group zero in BSD (to which the major system-internal users like root belong) is 'wheel'. Some vendors have expanded on this usage, modifying Unix so that only members of group 'wheel' can go root.

wheel bit // n.

A privilege bit that allows the possessor to perform some restricted operation on a timesharing system, such as read or write any file on the system regardless of protections, change or look at any address in the running monitor, crash or reload the system, and kill or create jobs and user accounts. The term was invented on the TENEX operating system, and carried over to TOPS-20, XEROX-IFS, and others. The state of being in a privileged logon is sometimes called 'wheel mode'. This term entered the Unix culture from TWENEX in the mid-1980s and has been gaining popularity there (esp. at university sites). See also root.

wheel of reincarnation //

[coined in a paper by T. H. Myer and I.E. Sutherland "On the Design of Display Processors", Comm. ACM, Vol. 11, no. 6, June 1968)] Term used to refer to a well-known effect whereby function in a computing system family is migrated out to special-purpose peripheral hardware for speed, then the peripheral evolves toward more computing power as it does its job, then somebody notices that it is inefficient to support two asymmetrical processors in the architecture and folds the function back into the main CPU, at which point the cycle begins again.

Several iterations of this cycle have been observed in graphics-processor design, and at least one or two in communications and floating-point processors. Also known as 'the Wheel of Life', 'the Wheel of Samsara', and other variations of the basic Hindu/Buddhist theological idea. See also blitter, bit bang.

wheel wars // n.

[Stanford University] A period in larval stage during which student hackers hassle each other by attempting to log each other out of the system, delete each other's files, and otherwise wreak havoc, usually at the expense of the lesser users.

White Book // n.

1. syn. K&R.