sentences:  Ad hoc syntax requires context to interpret ambiguous syntax, for example "<=" could be "is implied by" or "less than or equal to", and "dy/dx" is likely to denote a derivative, but strictly speaking could also mean a finite quantity "dy" divided by "dx".Unicode improves the support for mathematics, compared to ASCII only.Markup languages optimized for computer-to-computer communication include MathML, OpenMath, and OMDoc.