One basicly only needs a series of NAND-gates to construct any other gate.

The example above shows how to create a AND-Gate from NANDs.

Next easy example depicts how to create a NOT-gate.

Using both examples from above one can create an OR-gate.

Check out my last entry on gate delay: https://ldjam.com/events/ludum-dare/46/tyson-lee-keep-it-alive-edition/using-gate-delay-creatively

Come tinker and play at: https://ldjam.com/events/ludum-dare/46/tyson-lee-keep-it-alive-edition