BLIS/COBOL

{{See also|BLISS (programming language)}}

{{Infobox OS

| name = BLIS/COBOL

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| supported_platforms = Data General Nova and Data General Eclipse 16-bit minicomputers

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| programmed_in = COBOL

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| working_state = Historic

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BLIS/COBOL is a discontinued operating system that was written in COBOL. It is the only such system to gain reasonably wide acceptance.{{fact|date=December 2009}} It was optimised to compile business applications written in COBOL. BLIS was available on a range of Data General Nova and Data General Eclipse 16-bit minicomputers. It was marketed by Information Processing, Inc. (IPI), who regularly exhibited the product at the National Computer Conference in the 1970s and 80s. It was priced between US$830 and $10,000 depending on the number of supported users and features. In 1977, IPI boasted over 100 operational installations of the system worldwide.{{cite magazine | date = 13 June 1977 | title = IPI Advertisement | url = https://books.google.com/books?id=AGFRu5N2hloC&q=blis%2Fcobol&pg=PA118 | magazine = Computerworld | access-date = 17 December 2015

}}{{cite magazine | date = 31 May 1982 | title = NCC Preview '82 | url = https://books.google.com/books?id=QghOwt8qQsEC&q=blis%2Fcobol&pg=RA1-PA42 | magazine = Computerworld| access-date = 17 December 2015}}

By 1985, a version for the IBM PC existed called PC-BLIS.{{cite magazine | date = 8 July 1985 | title = PC-BLIS Note | url = https://books.google.com/books?id=h81aecuhbNMC&q=blis%2Fcobol&pg=PA40 | magazine = Computerworld| access-date = 17 December 2015}}

Originally, most operating systems were written in assembly language for a particular processor or family of processors. Non-assembler operating systems were comparatively slow, but were easier for revision and repair. One of the reasons for the C programming language's low-level features, which resemble assembly language in some ways, is an early intent to use it for writing operating systems. Similar goals led to IBM's development of PL/S. The high-level nature of COBOL, which created some problems for operating system development, was partially addressed in BLIS, since it was deliberately optimized for COBOL.