The short story is that the world is moving from unshielded to unshielded twisted pair also known as cat 8. This is more difficult to layout etc and expensive but with bandwidth up to 40gbps it’s really got way more upside to it. So great for new home builds. It costs $15 for two six feet lengths at Amazon.
As an aside there was a not quite standard cat7. You can ignore that and just jump to cat 8.
For budget installations moving to cat 6a because for very little cost you go from 250Mhz to 550MHz (10Gbps). So that’s a bit of future proofing particularly as WiFi backhaul jumps beyond gigabit Ethernet. It’s $15 for five 5-foot lengths at Amazon. So basically 2.5x less.
Also ideally, you want shielded mainly because of you going to every run power on Ethernet the runs will get hot. And as big a gauge as you can stand. 24AWG.
Finally if you’ve got an older home or office with unshielded cat 5e (1Gbps or 100Mhz) this won’t matter much. Just get else else cheapo unshielded cat 6. It’s about the same prove as cat 5e and at short ranges (like within a server rack can get to 10Gbls at 250Mhz)
