I:Autocad is a full featured collection of software tools used for designing and drafting. Developed by Autodesk, Inc. (Mill Valley, California) Released in December, 1982 II:Reasons why use Autocad -Accurate -Productive and efficient -Capable of sharing data III:Drawing Commands Keystrokes -Commands l -Line pl -Polyline rec -Rectangle c - Circle a -Arc el -Ellipse pol- Polygon e -Erase m -Move co -Copy ar -Array ro -Rotate tr -Trim ex- Extend o- Offset s -Stretch mi -Mirror f -Fillet cha -Chamfer J- Join Br -Break sc -Scale po -Point spl -Spline la -Layer mt -Mtext dim -Dimension h -Hatch ch -Properties lw -Line weight IV:Entering points in Autocad -Absolute coordinates -Relative rectangular coordinates / relative coordinates -Relative polar coordinates / polar coordinates V:2 Types of Array -Rectangular array -Polar array VI:Layer properties -Status -Name -On -Freeze -Lock -Color -Linetype -Lineweight -Plot style -Plot -Description VII:Dimension a.Basic Types: -Linear -Angular -Radial -Ordinate -Arc length b.Parts of Dimension: -Dimension text -Dimension line -Arrowheads -Extension line -Center mark -Center lines