Brigadoon - An Occasional Corner on the Internet
Security Sensors
Designed by Mark Little
Security sensors come in all shapes, sizes and complexity, ranging from a simple switch through microwave and infrared detectors to motion detecting video cameras.

How much time and effort one wants to expend on a security system depends on what is being protected and where it is stored. In most cases, people aren't protecting multi-million dollar irreplaceable works of art, so the security system does not need to cover all eventualities, rather, it needs to cover the most common the most common domestic break-ins.