What are the main differences between a class and an interface in Kotlin?

• Class: can contain properties (states) and functions (behavior). It can be abstract, open (for inheritance), or final. Constructors define how objects are created. Supports inheritance from one class and multiple interface implementations.
• Interface: defines a behavior contract that classes must implement. Can contain abstract function and property declarations, as well as functions with implementations (Java 8+). Cannot contain states (properties with backing fields). A class can implement multiple interfaces. Does not have constructors.

Comparison table:

Aspect	Class	Interface
State	Can have properties with values.	Cannot have properties with values (only abstract).
Constructors	Can have.	Do not have.
Implementation	Can provide full implementation.	Provides partial or full implementation (with default methods).
Inheritance	Inherits from one class.	Implements multiple interfaces.
Initialization	Can be instantiated.	Cannot be instantiated directly.
Type	Concrete or abstract.	Only a behavior contract.

Example of a class:

class Person(val name: String) { // class with constructor and property
    fun greet() {
        println("Hello, my name is $name")
    }
}

Example of an interface:

interface Greeter { // interface with method
    fun greet()
}

class EnglishGreeter : Greeter { // class implementing the interface
    override fun greet() {
        println("Hello!")
    }
}