What is the purpose of a data class in Kotlin?

The Data class in Kotlin is designed for creating classes whose main purpose is to store data. The compiler automatically generates useful standard methods for them:

• equals() and hashCode(): For comparing objects based on their properties.
• toString(): Represents the object as a string displaying its properties and their values.
• componentN(): For destructuring declarations (e.g., val (name, age) = user).
• copy(): Creates a copy of the object, possibly with some properties' values changed.

Example:

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

fun main() {
    val user1 = User("Alice", 30)
    val user2 = User("Alice", 30)
    val user3 = user1.copy(age = 31)

    println(user1) // Will output something like "User(name=Alice, age=30)"
    println(user1 == user2) // Will output true, as they are compared by properties
    println(user1 === user2) // Will output false, as they are different objects
    println(user3) // Will output "User(name=Alice, age=31)"

    val (name, age) = user1
    println("$name is $age years old.") // Will output "Alice is 30 years old."
}