Variables in Kotlin, differences with Java: 'var' vs. 'val'?

Question

I am trying to learn Kotlin. What is val, var and internal in Kotlin compared to Java?

In Java:

 RadioGroup radio         


        

Answer 1

In kotlin we can declare variable in two types: val and var. val cannot be reassigned, it works as a final variable.

val x = 2
x=3 // cannot be reassigned

On the other side, var can be reassigned it is mutable

var x = 2
x=3 // can be reassigned