Function

Tax returns are detailed financial reports filed annually with the Internal Revenue Service. They are detailed accounts of every dollar of income a person received during a given year so that income tax can be assessed. Based on the amount of income you've made and the conditions in which you live, the IRS can determine whether you've been taxed too much during the year and are entitled to a refund, or have been taxed too little and have to pay additional taxes. This is something that everyone making any kind of income must do every year.

The IRS

The Internal Revenue Service, a department of the United States Department of Treasury, is the agency that you report your taxes to. The IRS also is in charge of collecting taxes and mailing refunds. When you file your taxes to the IRS, what you are filing is a record of your wages from Jan. 1 to Dec. 31 of the previous year. If the IRS suspects that you've been falsely reporting your earnings to try to pay less taxes than you are supposed to, they can audit you. This means that they will require detailed receipts and financial statements from whatever period of time they deem necessary. If it is found out that you've made mistakes in your filing, you can be subject to fines as well as paying the back taxes they feel you owe.

Forms

Depending on what kind of income you are reporting, a dependent would still be required to report yearly earnings to the IRS. The most common forms needed for filing include the 1040, used by individuals with many deductions; or the 1040EZ, which is used by individuals with few, if any, deductions. You'll also need a W-2, which is the form you receive from any employers during the year.

Dependents

The definition of a dependent is someone who is reliant upon another person or people for their livelihood. An example of this would be a father and son, where the son is the dependent. The father would be able to claim the son on his income taxes and get tax breaks and refunds because of his son.

Aside from children, dependents can be spouses or grandchildren or blood siblings, adopted siblings, step-siblings or the children of any of those. They must be 19 at the end of the year for which you are filing, unless they are disabled, in which case any age limitations are waived, or unless they are full-time students, in which case they can be as old as 24.

Requirements

IRS Publication 501 lays out the guidelines for determining when a dependent must file a tax return. Find a link in the References section. Many scenarios are covered. For example: A return must be filed if a dependent earned more than a certain amount during the year -- $5,700 in 2010 for dependents under age 65, or $7,900 for dependents who were 65 or over and blind.