INTRODUCTION to COBOL

COBOL is a third-generation programming language, and one of the
oldest programming languages still in active use. Its name is an
acronym, for Common Business Oriented Language, defining its primary
domain in business, finance, and administrative systems for companies
and governments.

The COBOL 2002 standard includes support for object-oriented
programming and other modern language features.

COBOL programs are in use globally in governmental and military
agencies, in commercial enterprises, and on operating systems such as
IBM's z/OS, Microsoft's Windows, and the Unix/Linux families. In the
late 1990s, the Gartner Group, a data-processing industry research
organization, estimated that of the 300 billion lines of computer code
that existed, eighty percent — or 240 billion lines — were COBOL. They
also reported that more than half of all new mission-critical
applications were still being created using COBOL — an estimated
5,000,000,000 net new lines of COBOL code annually.

Near the end of the twentieth century the year 2000 problem was the
focus of significant COBOL programming effort, sometimes by the same
programmers who had designed the systems decades before. The
particular level of effort required for COBOL code has been attributed
both to the large amount of business-oriented COBOL, as COBOL is by
design a business language and business applications use dates
heavily, and to constructs of the COBOL language such as the PICTURE
clause, which can be used to define fixed-length numeric fields,
including two-digit fields for years.