GettyImages-102170169
The deadline to complete the Free Application for Federal Student Aid, or FAFSA, is Tuesday for the 2014-2015 school year. Getty Images

If you haven't submitted the Free Application for Federal Student Aid, or FAFSA, you might want to get on it. Tuesday is the deadline for completing your FAFSA for the 2014-2015 school year. The new award year for students attending college in 2015-2016 begins Wednesday. Confused? We'll break it down.

What is the FAFSA? The federal government awards about $150 billion annually to students via grants, loans and work-study programs. In order to figure out which students are eligible for which aid, the Education Department requires a FAFSA. States and colleges also use FAFSA data to determine financial assistance at their levels. You can complete it online, fill it out via PDF or request a paper version.

So what happens on Tuesday? Though the current academic year has finished almost everywhere, about 10 percent of students will still need to file for aid, according to Edvisors.com. In many cases this is because they didn't start school in August, as is traditional. FAFSA award years run from July 1 to June 30 annually, and the deadline is always the last day of that period. This year, it falls on Tuesday -- specifically, at midnight CDT. The FAFSA must be received by that time for federal consideration. Individual states have their own deadlines for FAFSA, but most of them have already passed.

What about aid for next year? Now might be a good time to file if you're looking ahead to the 2015-2016 school year. The FAFSA goes live on Jan. 1 each year, and money is given out on a first-come, first-served basis, Sallie Mae spokeswoman Martha Holler told CNN. The sooner you do it, the better, even though the FAFSA isn't technically due to the federal government until June 30, 2016. Remember, individual states have their own deadlines -- check those here.

How do I fill it out? The easiest way is to complete the FAFSA online here. It takes the average person about 20 minutes to fill it out. You’ll need your and your parents’ Social Security numbers, your driver’s license number, your family’s tax returns and information on other assets, according to the FAFSA site. See other FAFSA tips here.