Final answer:
A half-adder adds two bits without considering previous carry, whereas a full adder adds two bits along with a carry from a previous addition.
Step-by-step explanation:
The difference between a half-adder and a full adder lies in their capability to handle carry bits. A half-adder can add two single binary digits (bits) and provide the sum and carry as outputs. However, it cannot take into account an input carry from a previous stage. On the other hand, a full adder can add three bits—two principal bits and an additional carry bit from a previous addition—yielding both a sum and carry output that can be further propagated to subsequent stages in multi-bit binary addition operations.