The current Twisted Pair Categories:

Cat 5: 100MHz/2 pairs; 100 mbps (100 base TX). Cat 5e: 100MHz/4 pairs; 1,000 mbps (1000 base T). Cat 6: 250MHz/2pairs; 1,000 mbps (1000 base TX). Cat 6a: 500MHz/4 pairs; 10,000 mbps (10G base T).