His work features mathematical objects and operations including impossible objects, explorations of infinity, reflection, symmetry, perspective, truncated and stellated polyhedra, hyperbolic geometry, and tessellations. Although Escher considered that he had no mathematical ability, he interacted with mathematicians George Pólya, Roger Penrose, and Harold Coxeter; read mathematical papers by these authors and by the crystallographer Friedrich Haag; and conducted his own original research into tessellation.
Escher’s art became popular, both among scientists and mathematicians, and in popular culture. Apart from being used in a variety of technical papers, his work has appeared on the covers of many books and albums. He featured as one of the major inspirations of Douglas Hofstadter’s 1979 book Gödel, Escher, Bach.