What component is used to add two binary digits together including a carry bit?

The component used to add two binary digits together, including a carry bit, is the full-adder. A full-adder is designed to accept three inputs: two significant bits that are to be added and an incoming carry bit from a previous addition. It produces two outputs: the sum and the carry-out.

This characteristic enables the full-adder to handle additions that require consideration of previous carry values, which is essential in multi-bit binary addition scenarios. By effectively combining these inputs, the full-adder can facilitate the addition of binary numbers sequentially, allowing for more complex arithmetic operations in digital circuits.

In contrast, a half-adder only adds two single binary digits without accommodating a carry bit, which limits its use in situations where carry propagation is necessary. The binary adder and accumulator, while related to binary arithmetic operations, serve different functional purposes and do not specifically address the addition of inputs with carry considerations in the same way that a full-adder does.