The secret of the S7 Edge is in those curved sides that give it the Edge name. Samsung uses this feature to make the phone much narrower than it would be if it had a flat display. The S7 Edge also has curved glass on its back, making it much more comfortable to hold and easier to pick up.
Samsung also managed to make both S7 models water resistant. They can withstand up to 30 minutes under a meter and a half of water, so you don’t have to worry about your device being susceptible to the everyday tragedies of life.