HALF ADDER CIRCUIT:

It is a basic building block of a full adder and other circuits.It consists of two important parts as outputs sum and carry.it is a method of binary addition which consits if X-or gate and AND gate.The combination of two outputs is called the half adder circuit.

Sum-It is the Least Significant Bit 

Carry-It is the Most Significant Bit

It need two K-maps