If you are a US Citizen or Permanent Resident (i.e. Green Card holder), you will be taxed as “US Citizens” and you should file Form 1040.
Even if you were admitted into the US as non-immigrant, you may still be required to file as “US Citizens”.
Please see the “Non-Resident” page for additional information.
From this point forward in this page, all those who are required to file as “US Citizen” will be referred to as “US Residents”.
As a US Resident, your worldwide income is subject to US tax.
However, you are also entitled to enjoy the personal exemptions for yourself and your dependents as well as other tax credits and the Standard Deduction.