An ordered set is a collection of distinct elements arranged in a specific sequence. Unlike regular sets, where the order of elements does not matter, the arrangement in an ordered set is crucial. For example, in the ordered set 1, 2, 3, the sequence is important, and 3, 2, 1 represents a different ordered set. Ordered sets can be finite or infinite and are often used in mathematics and computer science. They can be represented using various data structures, such as lists or arrays. The concept is essential for understanding sequences, tuples, and other related structures in fields like set theory and combinatorics.