The AND operator is a fundamental logical operator used in programming and mathematics. It evaluates two or more conditions and returns true only if all conditions are true. For example, in a search query, using the AND operator between keywords ensures that results must contain all specified terms, enhancing the precision of the search. In computer science, the AND operator is often represented by the symbol "&&" in languages like Java and C++. It is essential in decision-making processes, such as in if statements, where multiple criteria must be satisfied for a specific action to occur.