An acronym created by the electronics industry for Mean Time Between Failures. This was an effort to establish a figure that gives an estimate of the reliability of a piece of equipment. The higher the MTBF rating, the longer the equipment should last. (The keyword is SHOULD!) For example, if the MTBF is 10,000 hours, the equipment should run, on the average, for 10,000 hours before failing. This rating is determined by the manufacturer who is also trying to make his product look attractive. Is there a conflict of interest here? Use these figures with some degree of caution.