Operators in SQL are used to perform operations and specify conditions in SQL statements. There are four main types of operators: arithmetic operators for numeric calculations, comparison operators for comparing values, logical operators for combining conditions, and set operators for combining result sets. Arithmetic operators include addition, subtraction, multiplication, and division. Comparison operators compare values for equality, greater than, less than, etc. Logical operators combine conditions with AND, OR, and NOT. Set operators such as UNION, INTERSECT, and MINUS are used to combine result sets from multiple queries.