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.
SMath Studio a freeware, closed-source mathematical notebook program developed by Andrey Ivashov. It is a program similar to Mathcad that is available for Linux, for Windows, Windows Mobile (Smartphones, PPC, and communicators), and is going to be ported to Java. The program’s interface is 'paper'-like and it contains numerous computing features like graphing functions in two or three dimensions, matrix operations including determinants, finding roots of polynomials and functions, numeric integration, and solving differential equations. SMath supports 18-th interface languages and can work with matrices, complex numbers, vectors, fractions, and infinities. Other features include the capability to create 2D and 3D graphs, availability of inserting text regions in a worksheet, unlimited size of worksheets and their quantity, support of parameters such as constants and user-defined parameters, and the capability to copy, paste, cut, and delete of expressions and/or parts of expressions. This application contains an integrated mathematical reference book.