// Air Traffic Service (ATS)
Generic term meaning variously, flight information service, alerting service, air traffic advisory service, Air traffic control service, Aerodrome control service.

Air Traffic Service : - Air Traffic Control Service
                                - Flight Information Service (FIS)
                                - Alerting Service

// On the maneuvering area between aircraft & obstruction ground control handle it.

// Flight Information Service
Giving advice & information useful for the safe and efficient conduct of flight.

//Alerting Service
A service provide to notify appropriate organization regarding aircraft in need of search and rescue aid, and assist such organization as required.

//Airspace :
1. Controlled Airspace = Control Area(CTA), Control Zone(CTR)
2. Uncontrolled Airspace = FIR, UIR
3. Aerodrome = ATZ, AFIS