The president's principal roles:
Approve federal laws (bills) created by Congress (Senate and House of Representatives), which is the legislative branch of government
Lead the nation's people, making sure citizens obey the laws and setting priorities for the country, including helping the Congress decide how the budget is spent
Manage the government, making sure that decisions and programs are being carried out effectively, with the help of the vice president and appointed cabinet members who head different departments (agriculture, commerce, defense, education, energy, health and human services, housing and urban development, interior, justice, labor, state, transportation, treasury, veterans affairs)
Represent the U.S. in meetings with leaders of other countries, including signing treaties and other agreements (with approval from Congress) on behalf of the U.S.
Command the U.S. military, including declaring war (with approval from Congress)