A Honeywell alarm system has 3 main programmed settings: off, stay, and away.
Off- Simply, the alarm is not armed. The security devices installed will not be triggered when engaged (a door opening). Environmental devices are still monitored during this time.
Stay- the perimeter devices are armed and the internal motion detectors are not armed. Typically the doors and windows will be armed allowing movement in the house. This function is primarily used at night or to accommodate a pet.
Away- arms the whole alarm. This included the motion detectors inside the house.