Everyone has a common sense idea about stripes (or strip).But we must be precisely about stripes and define them in a mathematical way.


D A stripe consists of two parallel lines and the area between them.

D A stripe runs ‘through’ the plane and has no beginning and no end.

D Running through the plane, a stripe can change its direction.

D In that case the distance between the parallel lines remains the same.


D The successive changes of direction are ‘the course of the stripe’.

D A stripe-course either has an open or a closed nature. In the latter case it is a ‘circuit’.


D If a stripe is a circuit, its shape has an outside and an inside. D> Its inside has the form of a point, a line, or a system of lines. In the latter case (some of) these lines can enclose an area.

striped pattern

D A striped pattern is a pattern composed of stripes which interlock.

D The various stripes in the pattern enclose each other or lie adjacent to each other.

D In a striped-pattern it is possible to determine a system of bisectors which regulates the course of the various stripes. This system divides the plane into area’s

D Two rules apply to this stripe course regulation:

- in an area all stripes run in the same direction;

- in adjacent areas stripes run in different directions.