Security systems come in two forms: the motion detector and the security laser. Use the NetHack view to reveal a motion detector’s scanning area, then hack and shut down either security system to pass by undetected. Be warned, the shutdown is only temporary, so if a security system’s hackable area is impossible to see without stepping into its cone of detection (e.g., if a motion detector is above a door you step through), you may need to trigger the alarm. Alarms cause all enemies to become hostile and can cause reinforcements to arrive.