A system state similar to that caused by an interrupt but synchronous to the system rather than asynchronous as in the case of an interrupt. There are a variety of conditions that can cause a trap to occur. Examples of such conditions include the attempted execution of an illegal instruction, or an attempt to access another user’s resources in a system that supports multiuser protection. The attempted operation is detected by the hardware and control is transferred to a different part of the system, usually in the operating system, which can then decide on what action to take.