At the Friday meeting on the 15th we showed 2 videos about the way a camera meters the scene.  It is good to understand how the camera thinks so when the situation occurs that the camera takes a wrong reading you need to compensate for that.  It may be too bright or too dark a subject since the camera wants to make everything middle grey.

www.youtube.com/watch?v=x-i-U67oCVc&t=547s  and 

www.youtube.com/watch?v=IPHNaGc8H9E