What is universal Gates?

What is universal Gates?

NAND and NOR gates are called universal gates because any one them can be used to realize of any logic expression.

NAND Gate

A NAND gate has the same effect as an AND gate followed by a NOT gate. Hence the output will be opposite of the AND gate. The diagram and truth table for a two-input NAND gate are shown in Figure 5.6.

NOR Gate

A NOR gate has the same effect as OR gate followed by a NOT gate. Hence the output will be the opposite of OR gate. The diagram and truth table for a two-input NOR gate are shown in Figure 5.7.

Basic gates (AND, OR, NOT) and universal gates (NAND, NOR) can be used in combination to make up digital computer circuits.