Linked from
The 10 pages that link to NAND gate, each with the reason it gives.
AND gateCompared with: Its output is the complement of the AND function.
NOT gateCompared with: NAND gates can implement inversion by tying their inputs together.
NOR gateCompared with: NAND and NOR are both universal gates but negate different operations.
XNOR gateCompared with: NAND is the complement of AND, not the complement of XOR.