Apple has been notorious for their lack of backwards compatibility. When OSX came out, any software purchased for the prior version was immediately made obsolete. Today, the latest iPhone 7, and the new MacBook Pro and MacBook say goodbye to some physical ports that may mean more money to substitute with new accessories for every location where you kept an extra.
The coveted MagSafe 2, still present in the Macbook Air, is sadly replaced by the USB-C port. Bottomline: you’ll have to get an expansion dongle in order to plug in all of your USB devices. The beautiful designed magnetic power plug, that ensured that accidental wire trips didn’t also send your laptop flying, is no longer available on the MacBook and MacBook Pro versions.