The tax year you are filing for is usually the year prior to the year taxes are actually filed, which makes sense because the government needs to know what you earned between January 1 and December 31 on your tax return. For example, taxes prepared in March of 2013 would be for tax year 2012.
Pay close attention to the complete title or description of tax software when you buy it either online or in the store. Be sure the software is for the right tax year. If you need to, you can also buy tax software for past tax years as well.