The circle is the generative shape of most Geometric Islamic Patterns, being subdivided into triangles, squares, polygons (pentagons, hexagons and octagons) and star-like shapes (6 to 16 pointed). Calligraphy and Foliate patterns are also used extensively and to a lesser extent Figures and Animals. In some ways you can see parallels between Islamic Art and traditional Celtic Art which also has complex geometry underlying its construction but is based on interlacing linear forms either as flowing knotwork, spiral and zoomorphic patterns, or angular key patterns.