Primitive data types

In Kotlin, everything is an object (reference type, not primitive type). We don't find primitive types, like the ones we can use in Java. This reduces code complexity. We can call methods and properties on any variable. For example, this is how we can convert the Int variable to a Char:

    var code: Int = 75 
    code.toChar() 

Usually (whenever it is possible), under the hood types such as Int, Long, or Char are optimized (stored as primitive types) but we can still call methods on them as on any other objects.

By default, the Java platform stores numbers as JVM primitive types, but when a nullable number reference (for example, Int?), is needed or generics are involved, Java uses boxed representation. Boxing means wrapping a primitive type into a corresponding boxed primitive type. This means that the instance behaves as an object. Examples of Java boxed representations of primitive types are int versus Integer or a long versus Long Since Kotlin is compiled to JVM bytecode...