The 'Jewels' mentioned in the movement are tiny, tiny synthetic rubies and are used as bearings between some of the moving parts.
[ELGIN] Why Watches Have Jewels
Generally speaking, manufacturers like to point out how many 'Jewels' the movement has as a sign of the build quality. In reality it doesn't tell you very much, but it sounds good!
I like the idea of the case of that "Submarine" one having a 'Display back' as well, ie: the back case has a glass too so that you can see the movement working.
PS: I notice some of those watches on that site have what's described as an ETA Movement:
eta
Just in case you were wondering, the Swiss firm of ETA is probably the biggest manufacturer of automatic movements in the world and supplies its products to Omega amongst others. many current Omega models use ETA movements with just a few cosmetic modifications.
Some of those watches look like a cheap way to get hold of a top grade Swiss automatic!