What the Hell is a "5" and a "9" Technique? Are they reffereing to thier gap assignments or how the players are starting out? And if so where the hell is the 9 gap.

Its a somewhat strange system for aligning defensive players commonly used by coaches.
On a center, a DL/NT can line up in a 0 technique (straight up), a strong shade (shoulder to the TE side) or a weak shade (shoulder away from the TE). On a guard, a DL can line up in a 2i (inside shoulder), 2 (straight up), or 3 (outside shoulder). On a tackle, a DL can line up in a 4i (inside shoulder), 4 (straight up) or 5 (outside shoulder). And against a TE a DL can line up in a 7 (inside shoulder), 8 (straight up), or a 9 (outside shoulder). Then you can line up your LBs off that, and generally a LB will add a 10s to the technique, for example an inside backer in a base 3-4 would probably be in a 30 (outside shoulder of the guard, off the LOS) technique. The gap assignments are still the same; between the C and OGs are the A gaps, OGs and OTs are B gaps, OTs and TEs are C gaps, and outside the TE the D gaps. So a 3 tech usually will be assigned the B gap to his side and so on.
So in the original post from the UT fan, a 0 technique (NG) is head up on the center and probably assigned to both A gaps, the 5s would mean both DEs are outside shoulder of the OTs and assigned C gaps and the OLBs are in 9s and assigned D gaps, outside shoulder of the TE. The MLBs would be in 30s and cover the B gaps.
In reality, we (as well as most defenses) will move our front. For example, we might move our defense strong, meaning the entire front (besides the playside OLB) will slide over a technique toward the TE. So the weakside OLB would be in a 5 (usually when there is no TE), the weakside DE in a 3, the NG in a strong shade, the strong DE in a 5, and the strong OLB in a 9. Then the MLBs would adjust, probably from a 30 to a weak shade off the LOS. Defensives will slide their fronts like this b/c it changes gap assignments. And often they'll line up in one set and may slant to a different technique ont the snap which changes their gap assignment.
All of this is done to confuse the offensive line and make it harder to block people; this movement by defenses (and more athletic defensive linemen) has brought about a lot of the zone blocking schemes in which offensive lineman basically block an area instead of man blocking schemes where they are assigned a specific defensive player with certain rules.