[link|http://thomas.loc.gov/home/lawsmade.bysec/formsofaction.html#bills|Library of Congress]:
A bill that has been agreed to in identical form by both bodies becomes the law of the land only after--

* 1. Presidential approval; or
* 2. failure by the President to return it with objections to the House in which it originated within 10 days (Sundays excepted) while Congress is in session; or
* 3. the overriding of a presidential veto by a two- thirds vote in each House.