What is Code of Federal Regulations (CFR) from pharmaceutical regulatory affairs point of view?

The Code of Federal Regulations (CFR) is the codification of the general and permanent rules and regulations (sometimes called administrative law) published in the Federal Register by the executive departments and agencies of the federal government of the United States.

The CFR is published by the Office of the Federal Register, an agency of the National Archives and Records Administration (NARA).
The CFR is divided into 50 titles that represent broad areas subject to Federal regulation.

Every regulation in the CFR must have an “enabling statute”, or statutory authority. The United States Code (U.S. Code) precedes the CFR and contains statutes enacted by Congress. The CFR contains regulations, which spell out in further detail how the executive branch will interpret the law.

Title 1: General Provisions
Title 2: Grants and Agreements
Title 3: The President
Title 4: Accounts
Title 5: Administrative Personnel
Title 6: Domestic Security
Title 7: Agriculture
Title 8: Aliens and Nationality
Title 9: Animals and Animal Products
Title 10: Energy
Title 11: Federal Elections
Title 12: Banks and Banking
Title 13: Business Credit and Assistance
Title 14: Aeronautics and Space (also known as the Federal Aviation Regulations, administered by the Federal Aviation Administration)
Title 15: Commerce and Foreign Trade
Title 16: Commercial Practices
Title 17: Commodity and Securities Exchanges
Title 18: Conservation of Power and Water Resources
Title 19: Customs Duties
Title 20: Employees’ Benefits
Title 21: Food and Drugs (administered by the US Food and Drug Administration and the US Drug Enforcement Administration)
Title 22: Foreign Relations
Title 23: Highways
Title 24: Housing and Urban Development
Title 25: Indians
Title 26: Internal Revenue
Title 27: Alcohol, Tobacco Products and Firearms
Title 28: Judicial Administration
Title 29: Labor
Title 30: Mineral Resources
Title 31: Money and Finance: Treasury
Title 32: National Defense
Title 33: Navigation and Navigable Waters
Title 34: Education
Title 35: Reserved (formerly Panama Canal)
Title 36: Parks, Forests, and Public Property
Title 37: Patents, Trademarks, and Copyrights
Title 38: Pensions, Bonuses, and Veterans’ Relief
Title 39: Postal Service
Title 40: Protection of Environment (administered by the United States Environmental Protection Agency)
Title 41: Public Contracts and Property Management
Title 42: Public Health
Title 43: Public Lands: Interior
Title 44: Emergency Management and Assistance
Title 45: Public Welfare
Title 46: Shipping
Title 47: Telecommunication (including rules administered by the Federal Communications Commission and other agencies)
Title 48: Federal Acquisition Regulations System
Title 49: Transportation
Title 50: Wildlife and Fisheries