FOR TRANSIT
| Company type | Software |
|---|---|
| Industry | Computer programming |
| Founded | 1957 |
| Founder | Bob Bemer |
| Products | FORTRAN variant for IBM 650 |
| Parent | IBM |
FOR TRANSIT (sometimes mistakenly written as FORTRANSIT) represents a variant of the FORTRAN programming language designed specifically for the IBM 650 Magnetic Drum Data-Processing Machine. This version was created under the leadership of Bob Bemer. While FORTRAN, recognized as the first high-level programming language, was originally developed for the IBM 704 in 1957, IBM aimed to provide a comparable programming solution for the older yet widely distributed IBM 650, which had sold over 2,000 units.
Though FOR TRANSIT maintained compatibility with the FORTRAN version for the IBM 704, it imposed certain restrictions: variable identifiers were confined to five characters maximum, and arrays were limited to two dimensions instead of three.
The compilation process involved multiple stages. Initially, source code was converted into an intermediate representation called IT (Internal Translator), a tool created in 1957 by Alan Perlis and his team at the Carnegie Institute of Technology. Subsequently, IT code was transformed into SOAP assembler instructions, which were finally assembled into executable machine code.
FOR TRANSIT remained exclusive to the IBM 650 platform; newer computer models possessed adequate capabilities to support comprehensive FORTRAN compilers without requiring this adaptation.
The term FOR TRANSIT might derive from several interpretations:
- FORTRAN-S(oap)-IT, highlighting its multi-step translation mechanism
- FOR TRANSIT(ion), emphasizing its function in facilitating migration toward the IBM 704
- FORTRAN's IT, indicating the integration of a FORTRAN interface with the IT compiler system