Binary coded decimal
Binary coded decimal is a way to encode numbers. The number is first split into digits, and each digit is then encoded in binary. This will result in a code from 0 0 0 0 (for "0") to "1 0 0 1" (for 9). The other codes (1010 to 1 1 1 1, representing the numbers 10 to 15) are not valid.
Binary Coded Decimal Media
A binary clock might use LEDs to express binary values. In this clock, each column of LEDs shows a binary-coded decimal numeral of the traditional sexagesimal time.