While you wait for the dopeness that is @mrwang I'll give you a very brief and concise response, just a few tidbits for your understanding. MrWang's video explanation will provide you with everything else you need to know for sure.
Bitshares is the cryptocurrency for the OpenLedger exchange. It takes care of any operating fees and like many exchanges that have their own crypto Bitshares has value. It's really simple to use and they have a lot of crypto that you'll only find on their dex.
In my opinion if you're on Steemit you should have an Open Ledger account because there are many users on this platform who have used O.L. to creat their own crypto such as the great Mr Wang as well as virtual grow, Steem trail and others.
I hoped that helped. I don't want to completely explain everything because Wang is gonna create some magic for you and he's really good at explaining so I don't want to take that experience away from you.
Regards.