The United States Code (USC) is a topical arrangement of all the federal statutes of the United States. When a bill becomes law, it is first published as a slip law and in the annual Statutes at Large. It is then divided into parts (if necessary) and codified under the appropriate titles of the USC, to make it easier to locate. A single law may end up in several different sections of the USC (sometimes even different parts, chapters, or titles), depending on the topical contents of the various pieces of the law.
There are several ways to look at the USC. The Office of the Law Revision Counsel published an official print set that contains nothing but the statutes themselves.
Additionally, both Thomson West and LexisNexis publish annotated versions of the USC that contain proprietary additions to the statutes, such as headnotes and Key Numbers. The Thomson West version is called United States Code Annotated, and the LexisNexis version is called United States Code Service. Both versions are available electronically, through WestlawNext and Lexis Advance, respectively.
One key difference between these two versions of the US Code is the source of the language itself. USCS uses the language provided in the Statutes at Large, whereas USCA uses the language from the official US Code. Typically, these should be the same, but on rare occasions it is discovered that slight changes occurred during the codification process. Generally, when the language is inconsistent, courts have held that the language in the Statutes at Large is controlling.
There are additional differences, as well:
(additional differences from http://lawlibguides.luc.edu/content.php?pid=128348&sid=1101468, firstname.lastname@example.org)
Both USCA and USCS use annual pocket parts to update each volume, and both occasionally publish softbound volumes during the year to update the pocket parts. The official US Code is updated with a bound supplement each year.
USCA: Within the pocket parts, use the table called "U.S. Code Sections Amended, Repealed, New, Etc." The table will provide a citation to the public law number that affected each changed section of the Code, and you can look up that law to see how the section was affected.
USCS: Each Advance pamphlet contains a table called "Table of Code Sections Added, Amended, Repealed, or Otherwise Affected," which can be used to check whether a particular section has been changed. These pamphlets are compiled annually in the Cumulative Later Case and Statutory Service.
You should always ensure you check online sources, as well, since print materials are typically slower to update than digital sources. If you don’t have access to WestlawNext or Lexis Advance, you can look at Congress.gov.
Each of the 50 titles in the USC contains law on a particular topic. Note that there is no Title 34, which dealt with the United States Navy prior to 1956. Additionally, Title 6 used to deal with surety bonds. Those provisions were repealed or moved to Title 31 in 1972 and 1982, and the new Title 6 was first introduced in the Homeland Security Act of 2002.
Title 1: General Provisions
Title 2: The Congress
Title 3: The President
Title 4: Flag and Seal, Seat of Government, and the States
Title 5: Government Organization and Employees
Title 6: Domestic Security
Title 7: Agriculture
Title 8: Aliens and Nationality
Title 9: Arbitration
Title 10: Armed Forces
Title 11: Bankruptcy
Title 12: Banks and Banking
Title 13: Census
Title 14: Coast Guard
Title 15: Commerce and Trade
Title 16: Conservation
Title 17: Copyrights
Title 18: Crimes and Criminal Procedure
Title 19: Customs Duties
Title 20: Education
Title 21: Food and Drugs
Title 22: Foreign Relations and Intercourse
Title 23: Highways
Title 24: Hospitals and Asylums
Title 25: Indians
Title 26: Internal Revenue Code
Title 27: Intoxicating Liquors
Title 28: Judiciary and Judicial Procedure
Title 29: Labor
Title 30: Mineral Lands and Mining
Title 31: Money and Finance
Title 32: National Guard
Title 33: Navigation and Navigable Waters
Title 35: Patents
Title 36: Patriotic and National Observances, Ceremonies, and Organizations
Title 37: Pay and Allowances of the Uniformed Services
Title 38: Veterans Benefits
Title 39: Postal Service
Title 40: Public Buildings, Property, and Works
Title 41: Public Contracts
Title 42: The Public Health and Welfare
Title 43: Public Lands
Title 44: Public Printing and Documents
Title 45: Railroads
Title 46: Shipping
Title 47: Telegraphs, Telephones, and Radiotelegraphs
Title 48: Territories and Insular Possessions
Title 49: Transportation
Title 50: War and National Defense
Title 51: National and Commercial Space Programs