The two categories of airspace are: regulatory and nonregulatory. Within these two categories, there are four types: controlled, uncontrolled, special use, and other airspace.

In the United States, the Federal Aviation Administration (FAA) classifies airspace into several categories to maintain safety and order in the skies. The four primary types of Regulatory Airspace include Class A, B, C, and D, while Class E is also regulatory but serves as "controlled" airspace that isn't one of the first four. Additionally, Prohibited Areas and Restricted Areas fall under the regulatory umbrella. Class A starts at 18,000 feet MSL and is exclusively for IFR traffic. Class B surrounds the nation's busiest airports (like JFK or LAX) and requires explicit ATC clearance. Class C is for moderately busy airports with a tower and radar control, typically featuring a 5-mile radius core and a 10-mile shelf. Class D is for smaller airports with an operating control tower. Pilots must adhere to specific equipment (like Mode C transponders) and communication requirements within these zones. Failure to comply with these regulations can result in severe penalties, as these boundaries are designed to prevent mid-air collisions and protect high-volume commercial flight paths.