What is a singleton class?

A singleton class is a class that is defined once and only once. This can be used to reduce the number of classes you need to define in your application, and it can also be used to reduce the complexity of your code. When you define a singleton class, you are declaring that the class is only ever going to be created once. This can be useful if you want to reduce the number of instances that your class will have to create, and it can also be useful if you want to reduce the complexity of your code. Singleton classes are often used when you need to create a single instance of a class, but you don't want that instance to be shared across multiple objects. For example, if you want to create a single instance of a class that represents an image, you might create a singleton class that represents that image.