Conditionals

if/else if/else work as usual, but in Kotlin if can also be used as an expression that directly produces a value.

Example: if as an expression

fun main() {
    val hour = 14
    val greeting = if (hour < 12) "Good morning" else if (hour < 18) "Good afternoon" else "Good evening"
    println(greeting)
}

Good afternoon

This single line replaces what a separate ternary operator does in languages like Java or JavaScript, Kotlin doesn't have a ? : ternary at all, since if/else used as an expression already covers the same need, arguably more readably once you're used to it.