d. High-Level Programming Languages. These languages are more
frequently used to write programs because they permit the programmer to concentrate
on the problem rather than the details of computer operation. They are easier to learn
and use, because they employ English-like terms and mathematical symbols. One
high-level language statement will accomplish the same result as a half-dozen or more
machine language instructions, mainly because the storage locations of data are
handled automatically rather than specified. High-level languages require less time to
write, provide better documentation, and are easier to maintain. They are somewhat
slower than low-level languages, and need to be translated by the computer into
machine language. Their advantages far outweigh the disadvantages as a program
development tool.
Figure 2-11. Machine vs. user orientation of programming languages.
2-11. HIGH-LEVEL LANGUAGES
a. FORTRAN (FORmula TRANslation). As stated earlier, high-level languages
are written for people, understood by people, and suited for specific applications.
FORTRAN was developed in 1954, specifically to solve scientific and mathematical
problems.
b. COMMON BUSINESS ORIENTED LANGUAGE. Common Business Oriented
Language was designed in 1960, with business data processing applications in mind.
Common Business Oriented Language is well- suited to the retrieval of data from files.
It can process files in an individualized manner, and look up indexed files efficiently,
for example, files indexed by client zip codes.
c. PROGRAM LANGUAGE, FIRST EDITION. Promoted in the mid-1960s by IBM
as a universal language, Program Language, First Edition (PL/I) combines the scientific
mathematical capabilities of FORTRAN with the business orientation of COBOL. Program
Language, First Edition is a very powerful language with many features. Less wordy than
COBOL, it is designed for use by both beginners and experienced users. Because it is such
a powerful language, a large amount of storage is required for its compiler. This means it can't
be used on smaller computers. But as mini- and microcomputers become more powerful,
subsets of PL/1 may be successfully applied.
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