1. An error in coding or logic that causes a program to malfunction or to produce incorrect results. Minor bugs, such as a cursor that does not behave as expected, can be inconvenient or frustrating, but do not damage information. More severe bugs can require the user to restart the program or the computer, losing whatever previous work had not been saved. Worse yet are bugs that damage saved data without alerting the user. All such errors must be found and corrected by the process known as debugging. Because of the potential risk to important data, commercial application programs are tested and debugged as completely as possible before release. After the program becomes available, further minor bugs are corrected in the next update. A more severe bug can sometimes be fixed with a piece of software called a patch, which circumvents the problem or in some other way alleviates its effects. See also beta test, bomb2, crash2 (definition 1), debug, debugger, hang, inherent error, logic error, semantic error, syntax error.
2. A recurring physical problem that prevents a system or set of components from working together properly. While the origin of this definition is in some dispute, computer folklore attributes the first use of bug in this sense to a problem in the Harvard Mark I or the Army/University of Pennsylvania ENIAC that was traced to a moth caught between the contacts of a relay in the machine (although a moth is not entomologically a true bug).
In computing, an error in a program. It can be an error in the logical structure of a program or a syntax error, such as a spelling mistake. Some bugs cause a program to fail immediately; others remain dormant, causing problems only when a particular combination of events occurs. The process of finding and removing errors from a program is called debugging.
Name of two rivers in E Europe: the West Bug rises in SW Ukraine and flows to the Vistula, length 768 km/480 mi, and the South Bug rises in W Ukraine and flows to the Black Sea, length 853 km/530 mi. + prikaži više

1. A problem, usually minor.
2. A brief surge in electrical power.