The universality of a gate means that it is possible to make each of the three basic gates with that gate. And since all the composite gates are made with the basic three gates, it is possible to make all the gates with that gate. This means that all Boolean functions can be performed publicly with that gate. And , at the end and knot, it is possible to create any logic circuit by combining three basic gates. Again , it is possible to make any circuit with just NAND gate. Because , it is possible to implement Or , End , and Not Gate with NAND gate. It is also possible to implement any circuit with Nor Gate. This is known as the Universality of Nanda and Knorr Gate.