You can create equivalents of AND, OR and NOT with only NAND, which is why it's possible for everything in a processor to be NAND gates only. https://en.wikipedia.org/wiki/NAND_logic
You can create equivalents of AND, OR and NOT with only NAND, which is why it's possible for everything in a processor to be NAND gates only. https://en.wikipedia.org/wiki/NAND_logic