Universal Gates: NAND and NOR

We can build any of the seven gates we introduced above using only NAND or only NOR gates, which makes each of these 2 gate types universal.

Computer circuit manufacturers benefit from this fact because:

1. It is cheaper to build NAND gates compared to other gates.
2. More complex circuits are easier to build with a single gate type vs. multiple gate types (NOT, AND, OR, etc.)

On the following slides, we prove that NAND and NOR are indeed universal gates by showing how we build each type of gate with them.