An air defense system can be divided into how many categories, depending on their role and type of target they are protecting?

An air defense system can be divided into 2 categories.

Explanation:

The U. S. military relies on a variety of missiles launched from finger-held to vehicle assembled systems. The Air Defense Artillery was the anti-aircraft weapons branch (for example, surface-to-air rockets).

The Missile Defense Agency's purpose is to protect stationed forces, allies, and partners, via a layered missile defence system, against hypersonic and ballistic missile threats of all kinds.

For example, two strong radars have been used on a landing pad in the Pacific to detect ICBM, another on Wake Island. The destination also was tracked by satellites equipped with infrared sensors.