Legal Definition
The Internal Revenue Service (IRS) is the federal agency responsible for administering the U.S. federal income tax system, collecting taxes, and enforcing the Internal Revenue Code. It is the primary body that establishes the rules for taxation and collects the revenue generated by the federal government.
Plain-English Translation
Imagine the IRS is like a big office that makes sure everyone pays their taxes. They are in charge of making sure people pay the right amount of money to the government, which is called income tax.