Repetition has a peculiar but generally very strong appeal, particularly when it is unfamiliar to the viewer. There is some connection here with one of the basic pleasures in music: there is a visual beat to pictures containing a repetitive theme, just as there is a musical beat. Visually, repetition comes across in two ways: as rhythm and as pattern. The difference between them is that rhythm is to do with movement across a picture (or more properly, the movement of the eye through a picture) while pattern is essentially static, and has to do with area. In a more technical way, you could think of these as dynamic repetition and spatial repetition.
• The Art Of Photography (OCA course book), Part 2, Rhythm and Pattern, p.95
Produce at least two photographs, one conveying rhythm, the other pattern. In rhythm there needs to be a repetitive sequence in the picture, so that the eye follows a particular direction. In the pattern image, there should be no boundaries to the pattern, that is, it should fill the frame.