The set of symbols that constitute strings in discrete mathematics is denoted by the symbol Σ, representing the alphabet. In contrast, Σ* denotes the set of all finite strings that can be formed from the symbols in Σ, including the empty string. The Kleene Star (*) indicates that the strings can consist of zero or more symbols. Therefore, Σ refers to the basic set of symbols, while Σ* encompasses all possible combinations of those symbols. Understanding this distinction is fundamental in the study of formal languages and automata theory.