FORTRAN, COBOL, Pascal and Ada

Hundreds of high-level languages have been developed, but only a few have achieved broad acceptance. FORTRAN (FORmula TRANslator) was developed by IBM Corporation in the mid-1950s to be used for scientific and engineering applications that require complex mathematical computations. FORTRAN is still widely used, especially in engineering applications.

COBOL (COmmon Business Oriented Language) was developed in the late 1950s by computer manufacturers, the U.S. government and industrial computer users. COBOL is used for commercial applications that require precise and efficient manipulation of large amounts of data. Much business software is still programmed in COBOL.

During the 1960s, many large software-development efforts encountered severe difficulties. Software deliveries were typically late, costs greatly exceeded budgets and the finished products were unreliable. People began to realize that software development was a far more complex activity than they had imagined. Research in the 1960s resulted in the evolution of structured programminga disciplined approach to writing programs that are clearer, easier to test and debug and easier to modify than large programs produced with previous techniques.

One of the more tangible results of this research was the development of the Pascal programming language by Professor Niklaus Wirth in 1971. Named after the seventeenth-century mathematician and philosopher Blaise Pascal, it was designed for teaching structured programming in academic environments and rapidly became the preferred programming language in most colleges. Pascal lacks many features needed to make it useful in commercial, industrial and government applications, so it has not been widely accepted in these environments.

The Ada programming language was developed under the sponsorship of the U.S. Department of Defense (DOD) during the 1970s and early 1980s. Hundreds of separate languages were being used to produce the DOD's massive command-and-control software systems. The DOD wanted a single language that would fill most of its needs. The Ada language was named after Lady Ada Lovelace, daughter of the poet Lord Byron. Lady Lovelace is credited with writing the world's first computer program in the early 1800s (for the Analytical Engine mechanical computing device designed by Charles Babbage). One important capability of Ada, called multitasking, allows programmers to specify that many activities are to occur in parallel. Java, through a technique called multithreading, also enables programmers to write programs with parallel activities.

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