The earned income tax credit (EITC) is a refundable credit. (A refundable credit is a tax credit that may provide a refund even if you have no tax liability.) The EITC is available to certain individuals and families who have low to moderate levels of earned income (from wages, salaries, tips, bonuses and/or net earnings from self-employment) and are taking care of at least one child and up to three qualified children. In certain cases, a taxpayer with low earned income and no children may also qualify.
The IRS has a variety of tools available to see if you qualify. You can access them at the IRS EITC Home Page.