One of the reasons we travel is to experience the little differences from place to place. One that is sort of subtle but pretty evident is how to interact with the person at the checkout. A few years ago in England my kids thought I'd gone crazy, we were in M&S or somewhere and I was chatting and joking with the checkout person. As we walked away my kids asked out I knew the checkout person, I replied, no that's just how it's done here. Well that was England, Edinburgh takes it to a whole new level. We were in the chipper (fish & chip shop) waiting for fish from the fryer, within minutes everyone was chatting, two guys came in for deep fried Mars bars, they were egging on other customers to challenge the staff to deep fry anything including a bottle of Becks beer. We got our fish, pies and chips and resolved to come back for deep fried Mars bars. The guys running the shop were truly happy to see us come back and shook Christopher's hand, not because he's going to Uni in Edinburgh next year, they shook his hand because he came back for the deep fried chocolatey goodness. Try this level of bonding in a shop in Boston and you will get a very blank stare. 
Edinburgh outside of the fryer is very picturesque, cultural and historic. We had a great run around the castle (including a session of Red Phone Box Selfie Madness), University, Sudent Halls. A climb to the top of the Scott memorial proved the world is indeed round: you CAN see Leith from the top. 
A grand city a great University and four years of opportunity.