This document is the collected studies of information on the robot audition software HARK (HRI-JP Audition for Robots with Kyoto Univ., “hark” means “listen” in medieval English). Chapter 1 describes outlines of the design philosophy, design strategy, individual technology and applications of HARK while it overviews the new horizon that the robot audition software and robot audition functions commencing with HARK open up.