DefinitionCombinatorics: a field of math mainly focused on counting, arranging, and choosing objects disregarding their order or structure. Covers permutations, combinations, combinatorial identities, and principles of counting. As such, combinatorics is widely used in computer science, cryptography, probability theory, and optimization. It provides methods for analyzing discrete structures and problem-solving with finite sets and arrays. Example: Combinatorial methods in cryptography are employed in the study of encryption algorithms to determine the maximum number of unique keys and the ease of breaking the encryption.