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                                                           Pascal 
         About the Tutorial 
         Pascal is a procedural programming language, designed in 1968 and published in 
         1970 by Niklaus Wirth and named in honor of the French mathematician and 
         philosopher Blaise Pascal. Pascal runs on a variety of platforms, such as Windows, 
         Mac OS, and various versions of UNIX/Linux. 
         This tutorial will give you great understanding of Pascal to proceed with Delphi 
         and other related frameworks etc. 
         Audience 
         This tutorial is designed for Software Professionals who are willing to learn Pascal 
         Programming Language in simple and easy steps. This tutorial will give you great 
         understanding on Pascal Programming concepts, and after completing this tutorial, 
         you will be at intermediate level of expertise from where you can take yourself to 
         higher level of expertise. 
         Prerequisites 
         Before proceeding with this tutorial you should have a basic understanding of 
         software  basic  concepts  like  what  is  source  code,  compiler,  text  editor,  and 
         execution of programs, etc. If you already have understanding on any other 
         computer programming language, then it will be an added advantage to proceed. 
         Copyright & Disclaimer 
         © Copyright 2015 by Tutorials Point (I) Pvt. Ltd.  
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         We strive to update the contents of our website and tutorials as timely and as 
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         Tutorials  Point  (I)  Pvt.  Ltd.  provides  no  guarantee  regarding  the  accuracy, 
         timeliness or completeness of our website or its contents including this tutorial. If 
         you discover any errors on our website or in this tutorial, please notify us at 
         contact@tutorialspoint.com 
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                                                                                                                                  Pascal 
                    Table of Contents 
                         About the Tutorial ................................................................................................................................... ii 
                         Audience ................................................................................................................................................. ii 
                         Prerequisites ........................................................................................................................................... ii 
                         Copyright & Disclaimer ............................................................................................................................ ii 
                         Table of Contents ..................................................................................................................................... i 
                    1.   OVERVIEW ........................................................................................................................... 1 
                         Features of the Pascal Language ............................................................................................................. 1 
                         Facts about Pascal ................................................................................................................................... 1 
                         Why to use Pascal?.................................................................................................................................. 2 
                    2.   ENVIRONMENT SET UP ........................................................................................................ 3 
                         Installing Free Pascal on Linux ................................................................................................................. 3 
                         Installing Free Pascal on Mac .................................................................................................................. 4 
                         Installing Free Pascal on Windows .......................................................................................................... 4 
                         Text Editor............................................................................................................................................... 4 
                    3.   PROGRAM STRUCTURE ........................................................................................................ 5 
                         Pascal Program Structure ........................................................................................................................ 5 
                         Pascal Hello World Example .................................................................................................................... 6 
                         Compile and Execute Pascal Program ...................................................................................................... 7 
                    4.   BASIC SYNTAX ...................................................................................................................... 9 
                         Variable ................................................................................................................................................... 9 
                         Functions/Procedures ............................................................................................................................. 9 
                         Comments ............................................................................................................................................... 9 
                         Case Sensitivity ..................................................................................................................................... 10 
                         Pascal Statements ................................................................................................................................. 10 
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                                                                                                                                  Pascal 
                         Reserved Words in Pascal ..................................................................................................................... 10 
                         Character Set and Identifiers in Pascal .................................................................................................. 10 
                    5.   DATA TYPES ....................................................................................................................... 12 
                         Pascal Data Types .................................................................................................................................. 12 
                         Type Declarations.................................................................................................................................. 12 
                         Integer Types ........................................................................................................................................ 13 
                         Constants .............................................................................................................................................. 13 
                         Enumerated types ................................................................................................................................. 14 
                         Subrange Types ..................................................................................................................................... 14 
                    6.   VARIABLE TYPES ................................................................................................................ 16 
                         Basic Variables in Pascal ........................................................................................................................ 16 
                         Variable Declaration in Pascal ............................................................................................................... 16 
                         Variable Initialization in Pascal .............................................................................................................. 18 
                         Enumerated Variables ........................................................................................................................... 19 
                         Subrange Variables ............................................................................................................................... 20 
                    7.   CONSTANTS ....................................................................................................................... 21 
                         Declaring Constants .............................................................................................................................. 21 
                    8.   OPERATORS ....................................................................................................................... 23 
                         Arithmetic Operators ............................................................................................................................ 23 
                         Relational Operators ............................................................................................................................. 24 
                         Boolean Operators ................................................................................................................................ 26 
                         Bit Operators ......................................................................................................................................... 28 
                         Operators Precedence in Pascal ............................................................................................................ 31 
                    9.   DECISION MAKING............................................................................................................. 33 
                         if-then Statement .................................................................................................................................. 34 
                         Syntax ................................................................................................................................................... 34 
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