If a condition is true, then Logical NOT operator will make it false. The Object Pascal extensions were added to Turbo Pascal with the release of version 5.5 in 1989. These extensions were then added back into the PC version of Turbo Pascal for version 5.5. [12][13] Turbo Pascal 5.5 had a large influence on the Pascal community, which began concentrating mainly on the IBM PC in the late 1980s. "Pascal-S: A Subset and Its Implementation", N. Wirth in Pascal – The Language and Its Implementation, by D.W. Barron, Wiley 1979. J. Welsh, W. J. Sneeringer, and C. A. R. Hoare, "Ambiguities and Insecurities in Pascal". C. A. R. Hoare: "Notes on data structuring". Sybil is an open source Delphi-like IDE and compiler; implementations include WDSibyl. B    Extended Pascal addresses many of these early criticisms. All of these languages were the work of Prof. Wirth, who wrote some of the best books on programming you find. Brian Kernighan, who popularized the C language, outlined his most notable criticisms of Pascal as early as 1981 in his article "Why Pascal is Not My Favorite Programming Language". In 1968, Wirth decided to abandon the ALGOL X process and further improve ALGOL W, releasing this as Pascal in 1970. Pascal became very successful in the 1970s, notably on the burgeoning minicomputer market. Since the early 1990s, however, most of the varieties seem condensed into two categories: ISO and Borland-like. This left an opening for newer languages. It could only do addition and subtraction, with numbers being entered by manipulating its dials. Jon Udell, Crash of the Object-Oriented Pascals, BYTE, July, 1989. While very popular in the 1980s and early 1990s, implementations of Pascal that closely followed Wirth's initial definition of the language were widely criticized as being unsuitable for use outside teaching. The French mathematician and physicist Blaise Pascal. PascalCase is a naming convention in which the first letter of each word in a compound word is capitalized. It is named in honour of the French mathematician, philosopher and physicist Blaise Pascal. Pascal allows the following types of operators − It implements a subset of full Pascal. This is in contrast to other languages, such as PL/I, C etc. Britannia Kids Holiday Bundle! The set operators can then be implemented efficiently as bitwise machine code operations. The Multum port was developed – with a view to using Pascal as a systems programming language – by Findlay, Cupples, Cavouras and Davis, working at the Department of Computing Science in Glasgow University. However, the addition of ALGOL-like empty statements in the 1973 Revised Report and later changes to the language in ISO 7185:1983 now allow for optional semicolons in most of these cases. Although Pascal resembled ALGOL in notation, it provided the ability to define data types with which to organize complex information, a feature beyond the capabilities of ALGOL as well as FORTRAN and COBOL. which use the semicolon as a statement terminator. It is similar to the AND operator, however, it guarantees the order in which the compiler evaluates the logical expression. On IBM PCs, the Borland standards Turbo Pascal and Delphi have the greatest number of users. Called Boolean AND operator. On top of ALGOL's scalars and arrays, Pascal enabled defining complex datatypes and building dynamic and recursive data structures such as lists, trees and graphs. IP Pascal was an implementation of the Pascal programming language using Micropolis DOS, but was moved rapidly to CP/M-80 running on the Z80. Pascal has certain unique types like the set type, and user-defined types are defined from other types using the type declaration. Much of the history of computer language design during the 1960s can be traced to the ALGOL 60 language.