Static attributes
1.static can be used to modify attributes.
2. Attributes modified by static are called static attributes or class variables and static variables.
3. Syntax: access modifier static data type variable name; access modifier static data type variable name = value;
4. Note: the access modifier and static are in no order.
5. Features: It has nothing to do with how many objects are created, and it is a common attribute of the whole class.
6. Use object name, static attribute name, and static attribute name (recommended).