What the hell is a Lumen?

     The Lumen is the SI unit for measuring the brightness of a light. The lm abbreviation stands for Lumen(s). A 60 watt incandescent light bulb will put out around 800 lumens, while a 15 watt Compact fluorescent bulb will do the same, and so will a 10 watt LED. I typically use a 35 Lumen headlamp while camping. It, like many others uses an LED, and the 35 lumens is more than sufficient.