Cobol - Computer and Information Science

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COBOL. COBOL (Common Business Oriented Language) was one of the earliest high- ... Institute (ANSI) developed a standard form of the language in 1968.
George Iashvili Date 2/24/2003 CIS 24

professor Kopec

COBOL COBOL (Common Business Oriented Language) was one of the earliest highlevel programming languages. It was developed in 1959 by a group of computer professionals called the Conference on Data Systems Languages (CODASYL). It was the second compiled language. (The first was FORTRAN.) Since 1959 it has undergone several modifications and improvements. In an attempt to overcome the problem of incompatibility between different versions of COBOL, the American National Standards Institute (ANSI) developed a standard form of the language in 1968. This version was known as American National Standard (ANS) COBOL. In 1974, ANSI published a revised version of (ANS) COBOL, containing a number of features that were not in the 1968 version. In 1985, ANSI published still another revised version that had new features not in the 1974 standard. The language continues to evolve today. Object-oriented COBOL is a subset of COBOL 97, which is the fourth edition in the continuing evolution of ANSI/ISO standard COBOL. COBOL 97 includes conventional improvements as well as object-oriented features. The Cobol language itself has evolved over the years to keep up, although still not quite to the level of Pascal or even PL/1. Structured Cobol versions such as Cobol II on the IBM mainframe introduced real structure termination (such as the End-If) and BeginEnd type statement groups (in-line Performs) so that periods are no longer as necessary. The case structure (Evaluate) was implemented to replace the Computed GoTo. Further

George Iashvili refinements added local nested procedures and standard predefined functions. Some versions of Cobol even support recursion. Pointers were also added to greatly simplify interfacing with subsystems like CICS and IMS and using linked lists. These improvements make it much easier to write good quality, modular, structured programs. COBOL is often used as the Y2K (Year 2000 problem) solution because of its ability to store 4 digit years in the file data. There are currently many companies employing COBOL programmers for massive amounts of money to help them prepare for the future. Without going into depth on the Y2K problem, it can be explained as follows. Most computers store the date information in a file as YYMMDD, (Year/Month/Day each with 2 digits). COBOL can save the year as follows: YYYYMMDD which makes it a valuable resource for businesses that need to plan into the future.