I see people using these types of snorkels a lot in our pool and I am wondering what their purpose is for training. Not having a swimming background, I am not really sure what their benefit is for swim training, other than taking the complication of a breathing pattern out of your stroke. What kind of exercises/drills would you do with a swimming snorkel?

Exactly, it takes the
Exactly, it takes the breathing out of the equation, so you can concentrate on other things. I use them all the time. I do a lot of pull descending pace sets with a snorkel. Personally, I use them to work on my catch. Anytime you do drills where you want to work on what is happening underwater, a snorkel works well, since you can watch it as well. I love mine.
I also use one when I'm
I also use one when I'm working on my catch, or doing some sculling drills (again, for a better catch).
I'll also so some race pace 25s with a snorkel and really concentrate on not crossing the centr line on my pull through.
Basically the purpose of
Basically the purpose of using a swimming snorkel in training is that it has the potential to increase lung strength via increased resistance to inhalation also it limits head movement.
Snorkels are good for two
Snorkels are good for two things:
Working on technique, so you're focusing just on your rotation and pull without worrying about breathing. It's also good for doing drills with.
Kick - It's very good for working your kick so you don't need to lift your head for breathing.
Not a required accessory, but can be good to use.