A half adder is a digital logic circuit that performs binary addition of two single-bit inputs, A and B, and provides two outputs, SUM and CARRY. The SUM output is the least significant bit (LSB) of the result, which is the XOR of the two inputs A and B. The CARRY output represents the carry bit that is generated when adding the two inputs and is the AND of the two inputs A and B). The half adder can be implemented using basic gates such as XOR and AND gates. Half adders are used in information processing applications like digital signal processing, data encryption, and error correction. They are also used in address decoding circuits to generate the address of a specific memory location.