This publication discusses some tax rules that affect every person who may have to file a federal income tax return. It answers some basic questions: who must file; who should file; what filing status to use; how many exemptions to claim; and the amount of the standard deduction. Who Must File explains who must file an income tax return. If you have little or no gross income, reading this section will help you decide if you have to file a return. * If you were born before January 2, 1947, you are considered to be 65 or older at the end of 2011.**Gross incomemeans all income you received in the form of money, goods, property, and services that is not exempt from tax, including any income from sources outside the United States or from the sale of your main home (even if you can exclude part or all of it). Do not include any social security benefits unless (a) you are married filing a separate return and you lived with your spouse at any time during 2011 or (b) one-half of your social security benefits plus your other gross income and any tax-exempt interest is more than $25,000 ($32,000 if married filing jointly). If (a) or (b) applies, see the Form 1040 instructions to figure the taxable part of social security benefits you must include in gross income. Gross income includes gains, but not losses, reported on Form 8949. Gross income from a business means, for example, the amount on Schedule C, line 7, or Schedule F, line 9. But in figuring gross income, do not reduce your income by any losses, including any loss on Schedule C, line 7, or Schedule F, line 9.*** If you did not live with your spouse at the end of 2011 (or on the date your spouse died) and your gross income was at least $3,700, you must file a return regardless of your age.Who Should File will help you decide if you should file a return, even if you are not required to do so. Filing Status helps you determine which filing status to use. Filing status is important in determining whether you must file a return, your standard deduction, and your tax rate. It also helps determine what credits you may be entitled to. Exemptions, which reduce your taxable income, are discussed in Exemptions . Exemptions for Dependents explains the difference between a qualifying child and a qualifying relative. Other topics include the social security number requirement for dependents, the rules for multiple support agreements, and the rules for divorced or separated parents. Standard Deduction gives the rules and dollar amounts for the standard deduction — a benefit for taxpayers who do not itemize their deductions. This section also discusses the standard deduction for taxpayers who are blind or age 65 or older, and special rules for dependents. In addition, this section should help you decide whether you would be better off taking the standard deduction or itemizing your deductions. How To Get Tax Help explains how to get tax help from the IRS. This publication is for U.S. citizens and resident aliens only. If you are a resident alien for the entire year, you must follow the same tax rules that apply to U.S. citizens. The rules to determine if you are a resident or nonresident alien are discussed in chapter 1 of Publication 519, U.S. Tax Guide for Aliens.