It’s a version of Windows 10 targeted at businesses that choose to run Windows on “Internet of Things” devices. It is a “Long Term Service Channel” release that receives primarily security updates (little to no features updates), because the devices that will use this need to be in service for a very long time. Enterprise Windows typically activates with a licensing server that’s subscription based. But you can use the “Microsoft Activation Scripts” to activate it as if it were a retail copy you pick up the store.