Actually, Allen Razdow of MathSoft was the creator of MathCad, an engineering computation program written in DOS and released during the late Eighties. It's the first computation tool that allowed live edits into the mathematical notation while the program automatically ran calculations with instantaneous answers. The Parametric Technology Corporation (PTC) bought MathCad in 2006 and added more features to this Windows-based engineering software. From simply verifying, documenting, and recycling calculations, MathCad now expanded its capabilities that include statistical functions, symbolic expressions, 2D and 3D parametric plots, curve and regression analysis, vector and matrix operations, and simultaneous equations. Users may insert images and text aside from Math equations into the worksheet or refer to computations and methods of analysis used in other worksheets with hyperlinks. Moreover, MathCad imports data files from other applications and exports the finished worksheets into MSExcel or MathML files.