1.13. 2D  Show[Graphics[ primitive ]]  

   The combined graphics could by obtained as a collection of simple objects called primitives. The primitive can be: point, line, ellipse, cube, etc. To draw the primitives one can use the function Show[Graphics[ primitive].

Primitive   Graphical object   
 
Point[ {x,y}]  Defines a planar point with co-ordinates {x,y}
Line [  { {x1,y1},{x2,y2},...}]  Defines a broken line by its vertices
Rectangle[{xmin, ymin},{xmax, ymax}]  Defines a rectangle by its vertices  
Polygon[  { {x1,y1},{x2,y2},...}]  Defines a planar polygon with co-ordinates of vertices {x1,y1},{x2,y2}, ...  
Circle [ {x,y} , r ]  Defined a circle with co-ordinates of the center and its radius
Disk [ {x,y} , r ]  Defines a disk with co-ordinates of the center and its radius  
Disk [ {x,y} , {r1,r2} ]  Defines an ellipse