Can you list the types of classes used in Kotlin?

The following class types are used in Kotlin:

• Regular classes — standard classes for describing objects.
• Abstract classes — classes that cannot be instantiated directly and may contain abstract methods.
• Interfaces — define a set of methods and properties that must be implemented by classes.
• Object declarations — singletons that create a single instance of a class.
• Companion objects — objects within a class that allow the creation of static members.
• Data classes — classes designed for storing data, automatically generating methods like equals, hashCode, toString, and copy.
• Nested and inner classes — classes declared within other classes; inner classes have a reference to the outer class.
• Sealed classes — classes with a limited set of subclasses, useful for expressing restricted hierarchies.

Example of a data class:

data class User(val name: String, val age: Int)