What is difference between object and data class in Kotlin?

Question

What is difference between data and object class in Kotlin, and what is the purpose of each?

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

and

object user {
    val name = ""
    fun printName(name: String) = "Hello, $name!"
}

Answer 1

object

object is Kotlin's way to create a singleton (one instance class) which is instantiated by the compiler.

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data class

A data class is like a usual class but with a few advantages/resctrictions (Source).

Advantages

• equals()/hashCode()
• toString()
• componentN()
• copy()

Those are created from the properties specified in the primary constructor.

Restrictions

• The primary constructor needs to have at least one parameter;
• All primary constructor parameters need to be marked as val or var;
• cannot be abstract, open, sealed or inner;
• (before 1.1) may only implement interfaces.