There is also a '1040EZ'.

Form 1040Ez is Income Tax Return for Single and Joint Filers with No Dependents. It's the easiest of the 1040 series. It's only one page. Form 1040A and Form 1040 are both two pages. But Form 1040A is easier than Form 1040.

what is the difference between the IRS 1040 and the IRS 1040EZ forms?

For federal income tax returns, you have three related forms: Form 1040EZ, Form 1040A, and Form 1040. Start by checking if you can meet all requirements stated regarding the use of 1040EZ and if you are okay with its limitations. If not, check the requirements and limitations of Form 1040A.

Form 1040 is a an annual tax form for the residents of the United States. It is also referred to as the "long form". Other 1040 forms available are 1040A (the short form) and 1040EZ.