AWK is a scripting language used for text processing and data manipulation. It operates on structured data, typically in files, by applying rules to patterns. An AWK script consists of rules that specify patterns and actions. It reads input line by line, matches patterns, and performs associated actions. AWK has built-in features like pattern matching, string manipulation, arithmetic operations, variables, arrays, and control structures. It supports regular expressions and provides useful variables like $0 (entire line) and $1, $2 (fields/columns). AWK is widely used for tasks like data extraction, formatting, reporting, and analysis due to its simplicity and efficiency in handling large datasets.