Please write Minimum 5 AutoCAD Commands. Which are very very usefull and you think other users might not know about these commands.

1. Qdim, for quick dimension

2. Extrim, for trim the unused lines at once defined by an object.

3. Filter, to select particular objects from many objects.

4. Blend, to prepare a Automatic Curve between two un attached curves.

5.Overkill, To remove overlapped lines.

In  3 D 

1- Copy of edges

2- Copy of face

3-3 D Mirror

4-2D Aline

5- Render

I would like to add as a basic to set up a drawing, they look difficult but are very handy basics:

mview: in Papespace make your vieport with mview

zoom: if you double click on the viewport with zoom, answer: .02XP you set the scale to1:50 etc.

Also with mview you can make different shapes of viewport and more viewport on the same page with different scales.

The rest is in the answers above

Also Xref, to attach basic drawings and overlays to keep your drawing small.

What you miss in AutoCAD15 is the layerbox, very handy, but just type LA and you have it.

You can always type the first to letters of the command on the command line. sometimes works handy.

m2p ........... draw anything between2 point

fs...............fast select

j...............join

sc re ...........scal to fit

imprint...........2d lines ... from3d

Copy,Move,Fillet,Hatch,Rotate...thank you

Good answers by experts but Mr. Shan answer is very useful.

1.)Arc

2.)Array

3.)chamfer

4.)Circle

5.)fillet

6.)mirror

7.)offset

Undo, Redo, Regen, Extend, Pan, DIMSCALE

I agree with Other Specialties.