Member Rara Avis
Okay, I've been doing some checking.
Cat5e (for "e"nhanced) is still 4 pair, 24 AWG (7/32) TC UTP, as defined in Standards Proposal 4195-b and finalized in ANSI/TIA/EIA 568A-5. The UTP in that definition stands for Unshielded Twisted Pair. It's really not much different than standard Cat5, but manufactured to higher specs. Cat5 is rated at 100M, while Cat5e goes to 350M. It is currently the highest "officially" rated standard, though it appears many outfits are already selling Cat6, Cat6e, and even Cat7 (even though there are no official specs for them). The Cat6 cables are called "solid UTP," which apparently means they use a solid wire rather than stranded, but the UTP shows that the solid wires are still twisted. I couldn't find a lot of information on Cat6/solid, but the larger wires would obviously decrease impedance.
The difference in price between Cat5 and Cat5e seems to be negligible, so it would make sense to go with the latter (gigabit Ethernet, here we come!).
It appears what you were originally talking about, Ali, is a new kid on the block called Cat5e "stranded cable." It has several small gauge wires in separate insulation sleeves, and is more flexible than twisted pair. Because of the flexibility and ability to make sharp right angles (something you shouldn't do with twisted pair), it seems to be popular for patch cables. The TIA/EIA 568A Standard limits the length of a stranded cable to 10 meters, for much the same reasons I mentioned before. Unless you need that kind of flexibility, however, I wouldn't recommend it. Even without the dangers of field induction, it seems to be more susceptible to moisture, too.
I found a real good page on Cat5 wiring (which would also apply to Cat5e). About half way down the page, under a heading of Detail checklist, is an excellent list of do's and don'ts.