Mainframes are high end commercial machines or computers, mainly used by large organizations, for important applications, usually mass data processing such as money transaction processing, census, Enterprise resource planning(ERP), consumer and industry statistics. The term initially originated from the primitive mainframes, which were housed in massive metal frames or boxes. Presently the term is used to distinguish less powerful systems and the high end commercial systems. These systems are run for several years without being suspended or interrupted, with repairs and even hardware and software up gradation taking place during regular operation. There were numerous mini-computer architecture and operating systems that were developed during 1970s but none of them are compatible with the mainframe computers. We have a different set operating systems run on the mainframes which include MVS, OS/390, z/OS ,OS/360 etc and also separate group of developed programming languages such as Fortron and COBOL.

There are several high-level programming languages used on mainframe systems for business applications such as COBOL, RPG (Report Program Generator), Fortran, APL etc. COBOL is the acronym for COmmon Business –Oriented Language. It is one of the most primitive high-level programming language primarily used in business, administrative systems for government and company, finance etc. Over 75% of world’s business runs on COBOL and it is considered to be the best implementation programming language for business applications. More or less every main organization from manufacturing real-time systems to finance applications rely on COBOL. RPG was initially designed as inquiry tool used to generate reports from information files which included sub-total reports and matching record but now IBM as enhanced it into a commanding programming language.

Latest version of RPG is RPG IV also known as ILE RPG. This was one of very few programming languages created for punch card technology which is being used even today. Fortran on the other hand is a general purpose imperative programming language used in scientific and numeric computational areas such as finite element study, climate modeling, computations in fluid dynamics etc. Fortran has dominated this area of programming since a long time and is still being used widely. IBM mainframe systems also run all major databases and enterprise transaction handling environments. Major databases include ORACLE and DB2. Database of ORACLE is a RDBMS acronym for relational database management system which has now become a major tool in database counting.

There is a huge requirement of mainframe educated graduates since a large number of mainframe professionals are expected to retire over the next 5 yrs. And in order to meet this requirement companies like IBM has been inspiring the fresh graduates to run machines which powers major business initiatives. So a candidate can very well do a course in any of the programming languages mentioned above from a reputed institute and can look out for opportunities as there are plenty.