Hyperbolic space is a space exhibiting hyperbolic geometry. The wave equation is the simplest example of a hyperbolic differential equation. Common methods of estimating include scalar, linear, hyperbolic and logarithmic. These cases give rise to the hyperbolic, parabolic or elliptic cylinders respectively. Research on multilevel techniques for hyperbolic partial differential equations is underway. It is possible to tessellate in non-Euclidean geometries such as hyperbolic geometry. There are two kinds of absolute geometry, Euclidean and hyperbolic. These models define a hyperbolic plane which satisfies the axioms of a hyperbolic geometry. It makes use of the special properties of parabolic and hyperbolic reflectors. There are however different coordinate systems for hyperbolic plane geometry. Escher made four "Circle Limit" drawings of tilings that use hyperbolic geometry. Thus they are conformal transformations with respect to the hyperbolic angle. It employs a different definition for "parabolic" and "hyperbolic". The use of anachronism in a rhetorical or hyperbolic sense is more complex. The discovery of hyperbolic geometry had important philosophical consequences.