Originally Posted by Brianog 
Sorry to be a pain asking this question
but could someone give me a brief definition of the difference between incident and reflected light metering. I am guessing that incident light is 'pure light' before it 'reaches' the subject. If so, I cannot understand why it would need to be measured.
reflected-light meters measure the light reflected by the scene to be photographed. all in-camera meters are reflected-light meters. incident-light meters measure the amount of light falling on the subject using an integrated sphere (usually, a translucent hemispherical plastic dome). you also have spot meters, which are reflected-light meters that measures light in a very tight cone, typically with a one degree angle.
they all have their use, and they all have their drawbacks.