A crash occurs when the computer issues a fault and deliberately halts that line of execution. The terms freeze, lock up or hang may refer to software that is actually still running but has erroneously wound up in an endless, internal loop that renders the program useless. In practice, the terms crash, freeze, lock up and hang are used synonymously. Seeinfinite loop.
Bad Hardware Can Look Like Bad Software
A serious hardware failure will stop a computer-based device that has no redundant components. For example, a short circuit on the motherboard will halt the operation; however, a failing memory cell can cause an instruction to point to an erroneous location, making it look like a software failure.