exception
An error condition that changes the normal {flow of control}
in a program. An exception may be generated ("raised") by
{hardware} or {software}. Hardware exceptions include
{reset}, {interrupt} or a signal from a {memory management
unit}. Exceptions may be generated by the {arithmetic logic
unit} or {floating-point unit} for numerical errors such as
divide by zero, {overflow} or {underflow} or {instruction
decoding} errors such as privileged, reserved, {trap} or
undefined instructions. Software exceptions are even more
varied and the term could be applied to any kind of error
checking which alters the normal behaviour of the program.
(1994-10-31)