What is 2015 United States Federal Budget?

Legal Definition
The 2015 United States federal budget is the federal budget for fiscal year 2015, which runs from October 1, 2014 to September 30, 2015. The budget takes the form of a budget resolution which must be agreed to by both the United States House of Representatives and the United States Senate in order to become final, but never receives the signature or veto of the President of the United States and does not become law. Until both the House and the Senate pass the same concurrent resolution, no final budget exists. Actual U.S. federal government spending will occur through later appropriations legislation that is signed into law.
-- Wikipedia