Most Americans are aware of the Internal Revenue Service, also known as IRS, especially around April 15 of each year. American citizens must complete and submit their Federal and state income taxes by the annual deadline due date of April 15.
According to Wikipedia, “The Internal Revenue Service is the revenue service of the United States federal government. The government agency is a bureau of the Department of the Treasury, and is under the immediate direction of the Commissioner of Internal Revenue, who is appointed to a five-year term by the President of the United States.” (citation: https://en.wikipedia.org/wiki/Internal_Revenue_Service)
This official collection showcases some of the resources produced by the Internal Revenue Service (IRS) for consumers and business professionals that may be involved in payroll, or tax preparation roles. You can also purchase some historical IRS Bulletin issues from past years to compare the tax actions, procedures, and rulings from previous years to today here: https://bookstore.gpo.gov/search/products?keywords=Internal+Revenue+Cumulative+Bulletin