What specific data types in Kotlin are you familiar with?

Kotlin has several specific data types that distinguish it from other languages:

• Nullable types: in Kotlin, variables by default cannot contain null. To allow null, you need to explicitly specify the type with ?, for example, String?.
• Any: the base type for all objects, similar to Object in Java.
• Unit: a type that indicates the absence of a return value, similar to void.
• Nothing: a type that has no values, used for functions that never return a result (for example, throw an exception).
• Data classes: special classes for storing data with automatically generated methods equals(), hashCode(), toString().
• Sealed classes: allow restricting the inheritance hierarchy, useful for expressing limited sets of types.

Example of a Nullable type:

var name: String? = null
if (name != null) {
    println(name.length)
}