mers, and is also used in organisations such as weather forecasters, financial trading, and in engineering simulations. Fortran programs can be highly optimised to run on high performance computers, and in general the language is suited to producing code where performance is important. Fortran is a compiled language, or more specifically it is compiled ahead-of-time. In other words, you must perform a special step called compilation of your written code before you are able to run it on a computer. This is where Fortran differs to interpreted languages such as Python and R which run through an interpreter which executes the instructions directly, but at the cost of compute speed.