Sets an invisible drawing boundary in the drawing area.

Any drawing in AutoCAD will have the drawing limits (Paper size). AutoCAD provides quick and easy way of creating drawing limits. 
Format =>Drawing Limits => or type  in Command  line limits  => then Enter using keyboard. 

The following prompts are displayed.

Lower-Left Corner

Specifies the lower-left corner for the drawing limits.

Upper right corner

Specifies a point in the drawing area that represents the opposite corner of the rectangular limits boundary.

On

Turns on limits checking. When limits checking is on, you cannot enter points outside the grid limits. Because limits checking tests only points that you enter, portions of objects such as circles can extend outside the grid limits.

Off

Turns off limits checking but maintains the current values for the next time you turn on limits checking.