The gear you use in a pool to learn to dive is first rate, top notch... ok, it's one step from the garbage can. They don't use up good equpiment in the pool. It's not that it's not safe, or usable, it's just old. But the pool is a fairly safe environment, and you can't be in it without an instructor, so it's not a big deal. Plus you get really hyped for the better stuff you rent for the openwater dives!
The first night, they had laid out lots of sets of equipment - a BCD (Buoyancy Compensation Device, also refered to as a BC), tank, regulator and octopus, and a dive gauge. The BC's are jackets with air bladders in them whose main design is to crush your ribs like cardboard... I mean to keep you floating on the surface, and so you can adjust your buoyancy when underwater. And to hold the tank. I got one that I didn't realize was too big until the third night, and it tended to crush my ribs like... well, it didn't fit and I didn't like it. But at the time I was too green to know how it was supposed to fit.
The rest of it was pretty similar, a thingie to stick in your mouth that supplies air, and another one for a spare, and a set of gauges. We climbed into the pool and started in. First thing he had us do was just put the regulator in our mouth and go under, so we could do it once, see how it was, and move on. It's an experience breathing underwater. Newbies tend to suck air pretty fast ("Hoovering" it, I've seen it called :-). Eventually, we're told, we'll be able to control our breathing better and make a tank last longer.
I don't remember the specific order of things, but we had to take our reg out of our mouth and drop it, then find it again, all the while exhaling. Rule number one of diving: NEVER STOP BREATHING! Serious injury can result, especially if you take a big ole' breath of condensed air underwater, then come up while holding your breath. Your lungs will overexpand, and that's not good. Plus there's the drowning thing, so we had to learn how to find our air if we lose it for any reason. And flooding and clearing our masks, which seems to be the hardest thing to do for a lot of people - read ScubaBoard, it's probably the most often asked question. And sharing air, in case one of us has a problem, breathing out of a regulator that's stuck open (which is a lot easier than it sounds), taking the gear off and putting it back on, dealing with cramps, and a dozen other things you may have to do underwater. And a dozen we will probably never do again. :-)
We did a total of 5 dives in the pool. On two nights, we had to refill our tanks, which constitutes another dive. But the instructor had a little book of moves he and his divemaster and/or instructor students had to verify we could do. We did 'em all. The worst was probably the 10 minutes we had to tread water at the end of the class. :-) We all made it through, but we glad when it was done, too.