Base

From FIRSTwiki

In FIRST LEGO League base is where the robot starts a match and the only place a team member may touch the robot during the match without a penalty. Within a match the robot starts in base before attempting one or more missions.

Base is an imaginary hollow shape formed by vertical walls that rise from the perimeter of the Base’s footprint (including the inside surfaces of the border walls), and by an invisible ceiling, typically 16in (40cm) high. (Base is a VOLUME---not an area.)