A distinct digit refers to a unique number in a given set or sequence. For example, in the number 1234, each digit (1, 2, 3, 4) is distinct because none of them repeat. However, in the number 1123, the digit ‘1’ is not distinct because it appears more than once.
Distinct digits are often used in mathematics and computer science to ensure that each number in a sequence is unique. This concept is particularly important in problems involving permutations, combinations, and unique identifiers.