How vectors are created

Basic shapes

 

	a rectangle is four straight paths connected by four 90° (right-angled) corners (lat. 'rectus' = right)
	a triangle is the same principle, connected by corners of less than 90°
	a polygon is the same principle, connected by corners of more than 90°
	a star is the same principle, connected by corners of, alternately, less than 90° and more than 90°
	an oval is a closed path made up of four curved segments, connected by four smooth points
	a spiral is an open path made up of arcs joined together, with ever-increasing radius

Graphics programmes provide tools to create these common shapes in a simple way, and the modifier keys adjust things while you work - e.g.

- shift constrains things to 90° angles, straight lines, symmetrical shapes and so on

- alt./option may start drawing a shape from the middle instead of the edge

- the spacer-bar may allow you to move the shape

- the up and down arrows may affect the number of sides a polygon has

animation, 155 Kb