They say that Ionization smoke detectors don't work as well as Photoelectric smoke detectors.

Who knew?

In fact, I didn't realize there was even a difference in smoke detectors. Period. I just figured a smoke detector is a smoke detector. But no...

Tests conducted by WTHR, local fire departments, university researchers and government scientists all show that in some slow burning fires, Ionization smoke alarms do not sound at all. Source

The sad truth is... with an Ionization smoke detector, you are more likely to die of smoke inhalation in a fire than you are if you had a Photoelectric smoke detector.

Okay then, what's the real difference between Photoelectric and Ionization smoke detectors? And how can you tell which one you have?