What is the purpose of the Office of Management and Budget?

The Office of Management and Budget (OMB) for short, was
created in 1970.  The purpose of this office is to help the President prepare the budget
for the federal government.  In addition, once the budget is passed, the OMB is supposed
to help the President to administer it.

The whole point of
having this office is to help the President have a relatively independent agency working
on budgetary matters.  Before the OMB existed, Presidents had to ask each agency for
advice on those agencies' budgets.  Of course, no agency would ever say they needed less
money.  When OMB was created, it was meant to help presidents look more objectively at
all the parts of government and try to come up with ways to save
money.