Cat 5e:
Twist per Inch: 3 to 4 
Gage: 24AWG
CMR rated: 350Mhz
Speed: 10/100Mbs
Cat 6:
Twist per Inch: 5 to 6 
Gage: 23AWG
CMR rated: 600Mhz
Speed: 10/100/1000Mbs
CCA (Copper Clad Aluminum)
This type of cable has an inner aluminum conductor coated with copper, and is much lighter than solid copper cables. Because CCA cable is manufactured at a much lower cost, it offers higher profits to contractors that sell this product.
Cat 7:
Twist per Inch: 5 to 6
Gage: 23AWG
CMR rated: 600Mhz
Speed: 10/100/1000Mbs/10Gbs
Pairs individually shielded
Copper Cabling