Codes are laws arranged by subject. When a law is codified it is combined with all the other laws on the same subjects and previous current laws and any ammendments to the law. The first volumes are the U.S. Constitution.
The Code of Federal Regulations is a codification of the general and permanent rules and regulations published originally in the Federal Register by executive departments and agencies of the federal government.
The Federal Register is the official vehicle for making the regulations and legal notices issued by the federal agencies and departments available to the public. These include federal agency documents, such as regulations (proposed, temporary, amended, and final) having general applicability and legal effect, documents required to be published by act of Congress, federal agency documents of public interest, meeting notices, and Presidential proclamations and executive orders.
You need to use both these publications to find the most up-to-date regulations. They update each other.
The official text and compilation of U.S. public and private laws.
Regulations contain the permanent regulations that have been adopted by the state agencies to implement, interpret, or make specific the law enforced or administered by the agency.