Ratings or classifications officially are used to help seed fencers into pool a in tournaments around the United States. You earn a rating by ended up in a certain place at a tournament with a given strength (measured by the number and variety of fencers with these given ratings). Since fencing is most often done in a tournament format with one winner - many fencers consider renewing or earning ratings as an acceptable consolation for a medal.
Earning a rating in fencing therefore depends on three factors: 2)how well you did, 3) how good is everyone else, 4) how well THEY did. For example, if you are in small event and you kicked ass, great! If the three best guys you didn't fence in direct elimination had an awful day - you might not get a rating. And you will be very angry. If you ever see a picture from a local tournament with an angry teenager with a gold medal around his neck - well, you know why.
In fact, more than any other sport - fencing rewards the people who on paper are supposed to win. Top seeds get the easiest pools, bottom seeds are fed to the lions. Therefore the top seed theoretically should be the top seed at the start of the direct elimination round AND have the easiest path to the final. If you are the top seed and you lose to the young upstart in the round of 16, you could bring down the whole tournament rating - and everyone will hate you. Seriously. Bad things will be said about you. You might get a reputation as the "pretty" one instead of the "good" one.
So, let's say you come into some money and you decide to outfit yourself and your five best college buddies in fencing kit and want to have a tournament. If the local USA Fencing Division board allows it, you can have an event! If you win, CONGRATS you are a brand new E rated fencer! So an E is a guy who can beat a roomful of rank beginners. Don't laugh, that is a tougher accomplishment than you might think. Even so, I wouldn't brag about earning it if you have been in the sport for more than six years.
Every E wants to be a D. Desperately. if you are a D, you theoretically become the top rated fencer in every National Division III (aka D and Under) tournament you enter. There are two common ways to earn a D: win a D rated event, or place highly in a much stronger A or B rated event.
The first option means beating everyone who is around your ability level in your DE path and getting the gold. And if these events didn't last all day, it might be the easier option. Plus, when new ratings are on the line, fencers tend to do a LOT better.
The second option basically means you beat most of the people in your pool, but got knocked out of DEs early. Now this is supposed to be the harder option; if your opponents got a good night's rest, didn't go out drinking, aren't sick, etc. If you are patient and focused, you might pick up touches at 9am that you'd never get at noon.
D, as you might have guessed, is for Desperate. Every D is dying to be a C. A C rated fencer is (or supposed to be) the top seeded fencer in National Division II (C and Under) competition. Cs, for now anyway, are also eligible for National Division I (C and above) competition. Div I is where the big boys play - current and former Olympians and National Champions, folks who take the sport extremely seriously. The C rating is the sweet spot. You can still beat up on Unrated fencers, and you can play with the big boys. Plus it is a rating where many fencers begin to acknowledge you as "good." You earn a C by entering a C rated competition and winning, or by losing in the quarterfinals of a large A rated tournament.
All Cs want to be As. Those who try and fail become Bs. The B is the middle child of fencing ratings. You aren't considered as good as an A, but you are barred from Div II competition. Many fencers that I have known dropped the sport after earning a B. In Georgia foil competition, many folks win a B rated tournament to become a B fencer. In Epee, one earns a B by losing either in the semifinal or final round of a large A rated event.
Everyone wants an A. On their term paper in college, on their performance evaluation (Acceptable) at work, and on the window of the restaurant they are dining. Fencing is no different. If you are an A fencer than you have won a large competition filled with strong fencers who also fenced well, or you did really well at a gigantic competition filled with badasses. In the Southeast, A fencers often get to fence for free in local tournaments, and are often courted into competing. Again, they get the easiest pools and the best path to allow them to renew their A rating. Plus they can brag to friends about being an A fencer - and those friends have a vague clue what that means.
Now these ratings only last four years or so. I for example am a B2007, so unless I find and win a tournament before July 31,2011 - I will become a C2011. Which isn't too bad, since in large tournaments the seeding is about the same. When I get my A this year, I will be an A2011 which would put mr at the top seed of local competition.