Final answer:
Instance variables are specific to each object of a class, while static variables are shared among all objects. The choice depends on the requirements of the program.
Step-by-step explanation:
Instance variables are variables that are specific to each object of a class. They hold unique values for each instance of the class and can be accessed and modified by the instance methods of that class. Instance variables are created when an object of the class is instantiated.
On the other hand, static variables (also known as class variables) are shared among all objects of a class. They are declared using the 'static' keyword and are associated with the class itself, rather than with individual instances. Static variables are created when the class is loaded into memory.
The decision to use instance variables or static variables depends on the context and requirements of the program. Instance variables allow each object to have its own state, while static variables allow data to be shared among all objects of a class. It is important to consider factors such as data encapsulation, data sharing, and memory usage when choosing between instance and static variables.