How is the equals() method implemented in the Any class and what does it compare?

In Kotlin, the class Any is the base class for all classes, similar to Object in Java. The equals() method in the Any class is implemented for reference comparison, meaning by default it checks whether two variables point to the same object in memory.

Example implementation (simplified):

open class Any {
    open fun equals(other: Any?): Boolean {
        return this === other // reference check
    }
}

Thus, if a class does not override equals(), the comparison is by reference. To compare by content, classes should override equals() themselves.