Other common types of packages are spreadsheet programs used to do relatively simple calculations, database management programs used to manage large amounts of data, and graphics packages used to present data. There are also many specific engineering software tools, such as computer aided design packages, statistical packages, and flowsheet packages. Modern software tools are typically very versatile and allow you a large range of opportunities. Still, there are problems that are so specialised or that combines so many different elements, that none of the existing packages will do the job properly. In this case, you must turn to a programming language, in order to create your own software tool.
Machine language is the language that is understood by the computer hardware.
Machine language is not very suited for writing large programs. High level languages such as Pascal, C, Fortran, and Basic allow you the flexibility of doing anything within the realm of the computer. Thus, the flexibility of a programming language comes at the price of having to develop long pieces of programming code. In terms of the types of computing required in designing, analysing, optimising, and controlling chemical process plants, however, matrix calculations are by far the most dominant. In fact, the existence of large libraries of programming code for solving matrix problems is one of the main reasons why Fortran until very recently remained the most common programming language used by chemical engineers.