... significant. BASIC is usually an interpretedlanguage; Pascal, C and Fortran are usually compiled. Figure 1.9 sum-marizes the operation of compiled and interpreted high level languages. 075065757X-ch001.fm ... achieved with so-called ‘high level languages’of which the best known are probably Pascal, FORTRAN and theubiquitous BASIC (and there are many, many languages: RPG,FORTH, LISP, CORAL and C to name ... modifications to cover changes in the oper-ations of the plant. These changes will be made by plant maintenancestaff, and must be made with minimal (preferably no) interruptions tothe plant production....