Types of Variables
- Instance Variable: Non-static fields are also known as instance variables because their values are unique to each instance of a class.
- Class Variables: A class variable is any field declared with the static modifier; this tells the compiler that there is exactly one copy of this variable in existence; regardless of how many times the class has been instantiated.
- Local Variables: Variables between the opening and closing braces of a method.
- Parameters: The Arguments of a method or a constructor.
- By convention it should start with the letter.
- Avoid $ and _ characters in the names.
- Whitespaces are not allowed.
- Keyword or any reserved word should not be used.
- For constants separate the words with the _.