Vectors can be created using the [b]Vector[/b] or [b]Vector from Point[/b] tools in the third[br]menu.[br][br][b]Vector[/b] joins two points [b]A[/b] and [b]B[/b] with the vector AB.  [br][br][b]Vector from Point[/b] will translate an existing vector so that it starts from a point.[br][br]Alternatively enter a set of coordinates with a lower-case name will create the object as a position vector, e.g. [b]v=(2,3,-1)[br][br]Line[A,v] [/b]will create a a line through point [b]A[/b] in the direction [b]v[/b].[br][br]Planes can be entered directly in Cartesian form: e.g. [b]2x+3y-z=2[/b].