What are the fields where you see maximum use of Autocad?

AutoCAD has maximum use in Engineering (mechanical and civil Engineering) but it also have importance in many other subjects like architect, CRD (Chemical reactor Design, a field of chemical engineering), aeronautical engineering and many other fields.

Any field which involves engineering.........

Architecture, Civil Engineering, Mechanical Engineering and Electrical Engineering. 

AutoCAD is mainly used in Architecture, Civil Engineering, Mechanical Engineering and Electrical Engineering. In Mechanical and Civil Engineering you can see maximum use of AutoCAD. 

AutoCAD is used mainly in Architecture, Electrical Engineering, Mechanical Engineering and Civil Engineering fields.

Engineering/Construction Field

I see that all :

Engineering mathematics.

Geometry & mechanical drawings.

Mechanical & Electrical Engineering .

Building Construction.

Engineering Serving and materials

Builders Quantity

are fields we can analysing and designing by autocad

any field which uses mechanical equipements to manufacture or construct or even build.

Mechanical, Architcure and civil in my opinion Autocad is most useful software