The Federal Register is the official journal of the federal government of the United States that contains government agency rules, proposed rules, and public notices. It is published every weekday, except on federal holidays. The final rules promulgated by a federal agency and published in the Federal Register are ultimately reorganized by topic or subject matter and codified in the Code of Federal Regulations (CFR), which is updated quarterly.

In law, codification is the process of collecting and restating the law of a jurisdiction in certain areas, usually by subject, forming a legal code, i.e. a codex (book) of law.