The ballots are in the mail.

Ballots for the 84th Academy Awards were mailed to the nearly 6,000 Academy members on Tuesday, the Academy has announced. Those voters now have until January 13 to decide upon their favorite films, performances and/or accomplishments of the year, and to get their choices back to PricewaterhouseCoopers in time for a week and a half of detailed and complex counting.

The basics about the Oscar ballots that were mailed on Tuesday: They're color-coded by category, and cover 15 of the 24 Academy Awards categories. (Nominations in the rest of the categories are decided by special committees or at specific AMPAS events.)

Best Picture ballots are white, with the other categories using generally muted colors.

While Best Picture ballots are tabulated using the new system, the other 14 categories use the straight preferential count, which uses a number of rounds to narrow the field down to the final five nominees.

On every ballot except the acting ballot, voters are asked to list the name of the film, not the name of the person who will actually be nominated. This will make things much easier for directors who want to vote for Michel Hazanavicius but will only need to write The Artist.

The reminder list of eligible films that accompanies most of the ballots includes film titles only, not names of potential nominees.

Members of the Actors Branch, though, are required to list the name of the actor and the name of the film -- and they're given complete leeway to decide if a performance belongs in the lead or supporting category (or even to put it in both if they're undecided).

If a performance actually gets enough votes to be nominated in both lead and supporting categories, it will receive the nomination in whichever category it drew the most support.

And given the way the system works, in only five categories does a film need more than 100 votes to be nominated for an Oscar. That's because nominations are made by the individual branches, not by the entire membership of the Academy.

The Actors Branch, with more than 1,100 members, is by far the largest. If every member were to vote, it would take just under 200 votes to secure a nomination in the four acting categories.

The next largest branches, the Producers Branch and the Executives Branch, with about 450 members each, only vote for Best Picture (as do Public Relations Branch members and Members at Large).

Directing, writing and sound categories require about 60 votes for a nomination; music requires about 40 for an Original Score nomination, with the Original Song category using a different process.

It goes all the way down to cinematography and film editing, which require between 30 and 40 votes, and makeup and hairstyling, which require only about 20 votes.

That doesn't seem like many for an Oscar nomination -- but remember, those are 20 top experts voting. It's the Academy's unofficial credo, when it comes to membership: quality, not quantity.