When a bill is passed in identical form by both the Senate and the House, it is sent to the president for his signature. If the president signs the bill, it becomes a law. Laws are also known as Acts of Congress. Statute is another word that is used interchangeably with law.
When the president signs a law, the law receives a number in the order in which it is signed. A citation to a public law looks like this: P.L.107-101, where 107 indicates this law was passed during the 107th Congress, and 101 is the numerical designation it received. A private law is designated similarly, but uses the term private law instead of public law.
Public and private laws are printed as slip laws–which are single sheets or pamphlets containing the text of the law. At the end of each session of Congress, slip laws are compiled into a single volume called U.S. Statutes at Large.
Most laws are eventually incorporated into the U.S. Code.