Question

What are the Advantages of AutoCAD over manual drawings?

Answer 1

The advantages of AutoCAD as compared to manual drawings are:

AutoCAD:

1. Can Quickly create drawings & designs
2. Makes the editing of already drawn maps easy
3. If a locality changes, the map is not to be made again (as in manual drawings you have to) but only the already saved file of that drawing in AutoCAD is edited and taken print of. 
4. Has Improved quality over hand drafting
5. Can be customized to suit the individual’s needs
6. Teaches a marketable skill

Answer 2

People have mentioned cost - yes it can be cheaper to produce a one off drawing with a pen and paper even with buying all the drawing tools however to produce more than say 5 drawings the time saved with a CAD system far outweighs the cost of the computer.
http://www.cesdb.com/autocad.html