a) This term is used in High Density Digital Recording (HDDR), or High Density Recording (HDR), or other such names and refers to the number of errors a specific magnetic tape may contain, and is expressed in errors per data bits, such as one in 106 or one error in one million data bits. b) The average probability of a digital recording system reproducing a bit in error. Note: IEEE 100 defines error rate as “the ratio of the number of characters of a message incorrectly received to the number of characters of the message received.” Bit error rates typical of current digital tape recording are: digital video tape, about 106; digital instrumentation tape, about 109; digital computer tape, about 1012.