Identifiers

• Identifiers
  -are tokens that represent names of variables, methods, classes, etc.
  -Examples of identifiers are: Hello, main, System, out.
  
• Java identifiers are case-sensitive.
  -This means that the identifier Hello is not the same as hello.
• Identifiers must begin with either a letter, an underscore “_”, or a dollar sign “$”. Letters may be lower or upper case. Subsequent characters may use numbers 0 to 9.
  
• Identifiers cannot use Java keywords like class, public, void, etc. We will discuss more about Java keywords later.

Coding Guidelines:

• For names of classes, capitalize the first letter of the class name. For example,
  ThisIsAnExampleOfClassName
  
• For names of methods and variables, the first letter of the word should start with a small letter. For example,
  thisIsAnExampleOfMethodName
  
• In case of multi-word identifiers, use capital letters to indicate the start of the word except the first word. For example,
  charArray, fileNumber, ClassName.
  
• Avoid using underscores at the start of the identifier such as _read or _write.