Hey guys, I haz been approved!!!
OK, so I am a filmmaker / director who has also worked in tons of other freelance positions on film sets, so if you have questions - ask away!
I'll start off with this:
Q: What is a gaffer?
A: They are responsible for setting the lights. They deal with the electricity, and they set the lights, and also collaborate with the cinematographer on the look created with the lights.
Q: What is the Best Boy?
A: There can be two kinds of Best Boy. One kind is Best Boy Gaffer, who is the Gaffer's right hand and basically runs cable between the lamps and the generator or electric source, and assists with lighting tweaks. There can also be a Best Boy Grip who works with the Key Grip on rigging and safety, and McGyvering stuff.