Primary Sources: Federal Statutory Law

A slip law is an official publication of the law and is "competent evidence," admissible in all state and Federal courts and tribunals of the United States (1 U.S.C. 113).

What is the difference between a public and private law?

Public Laws: Most laws passed by Congress are public laws. Public laws affect society as a whole. Public laws citations include the abbreviation, Pub.L., the Congress number (e.g. 107), and the number of the law. For example: Pub.L. 107-006.

Private Laws: Affect an individual, family, or small group. Private laws are enacted to assist citizens that have been injured by government programs or who are appealing an executive agency ruling such as deportation. Private laws citations include the abbreviation, Pvt.L., the Congress number (e.g. 107), and the number of the law. For example: Pvt.L. 107-006. 

The United States Code is the codification by subject matter of the general and permanent laws of the United States based on what is printed in the Statutes at Large. It is divided by broad subjects into 50 titles and published by the Office of the Law Revision Counsel of the U.S. House of Representatives and U.S. Government Printing Office. 

Since 1926, the United States Code has been published every six years. In between editions, annual cumulative supplements are published in order to present the most current information.

After each legislative session comes to an end, all slip laws for that period are collected and bound into a chronologically arranged, cumulative set generically referred to as session laws which are arranged exactly how they were enacted.  

Session laws are published in a series called the United States Statutes at Large which contains every law passed by Congress since it was established in 1789. The series is prepared by the Office of the Federal Register and each volume contains its own subject index and table of contents. Since 1991, a popular name index has been included.