Due to my recent interest in collecting Depression Glass, I have been doing a bit of research on the subject and I found some interesting tid bits of information like:
~It was distributed for free or at a low cost during the 1920's as a business promotion. Businesses like the Quaker Oats Company would place it in boxes of food so more people would buy their product (Think the toy in the Cracker Jacks box). Some movie theatres would hand them out at the door to thank their customers.
~It was primarily manufactured in the central and mid-west part of the U.S. because of the supplies.
~A second category of DG is called Elegant Glass, which is also a collectible and was an alternative to fine china during the 1920's to the 1950's, then cheap glassware and imported china became it's replacement.
I haven't yet discovered how you can recognize Depression Glass specifically but I hope to find more time for research in the future!