Chances are if you have a job, then you have received a Form W-2 in the past. This form is completed by your employer and it reports a year's worth of income, including tips and bonuses. At the beginning of the new year, as an employee you usually receive three copies reflecting income earned for the previous year. One copy is for filing with your federal tax return, the second is for filing with your state tax return, and the third is for your own records.
Disclosure: This sample form is for illustrative purposes only. Official form should be downloaded from the IRS website.