They want you to submit your photography to be evaluated for use as stock photography.
No bad images need apply.
Stock photography is a tough business.
You have to:
1. have a clear photograph while looking at it onscreen at 100 percent resolution (that means you must blow it up very large on your screen so much so that only a portion of the photo will show up on most screens at 100 percent resolution).
2. have engaging subject matter.
3. not infringe on any copyrights.
4. submit large files.
There are many more stipulations also, just check them out on the Web site.
Use Dreamstime as a photography teacher...
That's right you can use Dreamstime to critique each and every photo that you have taken.
Just submit the photo and their staff looks at it and tells you what's wrong with it in an email.
So...if you want to improve your photography, register and get started...
Oh, and as far as making money, the time you'll have to put in for the amount of money you make probably isn't worth it.