Drop Away Rests are designed to give you maximum arrow clearance, by basically not being in the way when your arrow passes by. They are a mechanically controlled rest and in general come in two types
Cable Driven: Where the quick release of the bow cases the rest to fall away
Limb Driven: Where the rest is pulled down by the rest returning to its un-drawn position.
Both have advantages over each other and both will produce great groups.
Drop away rests are used by archers of all types and all levels, from beginners and recreational archers to top level bowhunters and target shooters.