Calculated Fields vs Calculated Columns

How do you feel about honesty? Me. I'm a total fan! So, here goes. the only reason I am writing this post is so that I can link to it. from over on the Mr Excel Forums. While a bunch of my posts have been very not targeted at brand new folks, the people asking questions on the forum tend to be completely new to Power Pivot. They ask for a formula to do such and such. then, I have to ask if they mean a "Calculated FIeld" or a "Calculated Column". and then they gimme the ol' Ron Weasley look. Or at least, that is what they are doing in my head. I mean. I can't actually see them. But, I'm pretty sure most of them are, in fact, young red headed kids.. So, I am going to step back a bit and cover this basic concept. If you are one of those people from the forum. WELCOME! Sorry about calling you a red head. Unless you are a red head. In which case. oh never mind, let's just get on with it.