A Machine Spirit is a supernatural, animistic spirit believed by the adherents of the Cult Mechanicus within the Adeptus Mechanicus (and, from that source, by most other humans of the Imperium of Man) to inhabit and control any piece of machinery or technology in existence. The functioning, or lack thereof, of any machine is believed to be the result of its spirit's disposition. To keep their Machine Spirits happy and cooperative, operators therefore make numerous ritualised advances to the machinery. These rituals depend on the machine or technology at issue, but in most cases include various maintenance rituals and prayers of function. They may also occasionally include a sacrificial offering or libation. The number of rituals or the size of the offering is increased in value if the mach