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The  HelloWorld  class includes a  method  named  main(),  which  is declared  with  three  Java
                 keywords: public, static, and void. The main() method should look like this:
                                        public static void main(String args[])
                 In the main method:

                    public means the method is accessible from outside the class.
                    static means the method belongs to the class rather than to instances of the class.
                    void means the method does not return a value.
                 The parameter String[] args is an array of strings that can hold command-line arguments provided
                 when the program is executed from the command prompt. The name args is conventional but can
                 be replaced with any valid identifier.
                 In BlueJ, the main method can be defined without arguments, if necessary, though the standard
                 form includes String[] args.
                 The main method in this example contains a single statement:
                                     System.out.println(“Hello from TrackGPT”);
                 This statement outputs the text "Hello from TrackGPT" to the console. The System.out refers to
                 the standard output stream, typically the console or terminal window. The println() is a method
                 that prints the specified string and then moves the cursor to the next line.
                 The semicolon at the end of the System.out.println() statement marks the end of the line. It is
                 also known as the line terminator. Since the Java compiler ignores extra spaces and indentations,
                 it’s important to use a semicolon to indicate the end of each statement in Java.

                    BASIC FUNDAMENTALS OF JAVA

                 Like other programming languages, Java also provides some fundamental concepts which are
                 given below:
                    Identifiers
                    Keywords

                    Data Types
                    Literals
                    Variables
                    Comments

                 Let us discuss these in detail.
                 Identifiers

                 A Java program assigns an identifier, such as a class or method, to uniquely identify it. A program
                 uses it to identify variables, methods, classes, and other entities.
                 Rules for Naming Identifiers

                 These are the guidelines you need to follow when creating names for classes, methods, and
                 variables in Java:

                    An identifier can include letters, digits (0–9), underscores (_), and dollar signs ($).
                    An identifier cannot start with a digit.

                    Keywords cannot be used as identifiers.


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