Original sentence: Basically a software version of the Roland TB-303, 808, 909, etc.Basically it creates space between the sounds that you play in a set pattern to give it a certain musical flavor.It moves the sound fractions of seconds and bars to play in places that you could  not edit evenly using the other Reason tools.ReGroove Mixer - a sample programming device that adds groove to individual channels.Rebirth Input Machine - a receiving module for patterns created in ReBirth, another software by Propellerhead
Edited sentence: Each of the groove channels feature controls for groove amount, slide and shuffle plus more detailed settings.ReGroove Mixer - The ReGroove Mixer applies its timing magic non-destructively and in realtime, giving you freedom to adjust its settings - and fine-tune your groove - as your music is playing.The Reason soundbank comes with a great selection of groove patches, many of them created from analyzed recordings of real musicians as well as classic groovy tracks.You can lock all your tracks together into one unified feel, or you can apply different settings to up to 32 musical elements in your song, for ultimate control