Apple has a fistfull of dongles to adapt existing peripheral devices to its 12-inch MacBook Retina, which only has a single USB-C (non-Thunderbolt) port, and its new MacBook Pro models, which only have Thunderbolt 3 USB-C ports. Also announced (but not yet shipping) is a Thunderbolt 3 to Thunderbolt 1 or 2 adapter for the new MacBook Pros.
