An Arithmetic Logic Unit, or ALU, is a fundamental component of a computer's central processing unit (CPU). It performs basic arithmetic operations like addition and subtraction, as well as logical operations such as AND, OR, and NOT. The ALU takes input data, processes it according to specified instructions, and produces output results that are used in various computations. The ALU operates using binary numbers, which are the basic language of computers. It is essential for executing instructions from computer programs, enabling tasks ranging from simple calculations to complex algorithms. The efficiency and speed of an ALU significantly impact the overall performance of a CPU.