Singleton

a design pattern that restricts the instantiation of a class to a single object

Key Characteristics of a Singleton:

• One Instance: Only one object of the class can be created throughout the application’s lifetime. 
• Controlled Access: A specific method (often getInstance()) is used to retrieve the single instance, preventing direct instantiation. 
• Global Point of Access: The singleton instance is accessible from anywhere in the application.

Other facts

• Cannot be extended by other class
• Singleton can extend other class
• Cannot have a constructor