Section 2.1 Types and Variables

Every value has a type

Examples:

  String greeting = "Hello, World!";

  PrintStream printer = System.out;

  int luckyNumber = 13;        
    

Identifier: name of a variable, method, or class

Rules for identifiers in Java:

• Can be made up of letters, digits, and the underscore (_) character
• Cannot start with a digit
• Cannot use other symbols such as ? or %
• Spaces are not permitted inside identifiers
• You cannot use reserved words
• They are case sensitive