Basics

println("Hello, world")
var myVariable = 42                               // variable (can't be nil)
let π = 3.1415926                                 // constant
let (x, y) = (10, 20)                             // x = 10, y = 20
let explicitDouble: Double = 1_000.000_1          // 1,000.0001
let label = "some text " + String(myVariable)     // Casting
let piText = "Pi = \(π)"                          // String interpolation
var optionalString: String? = "optional"          // Can be nil
optionalString = nil

/* Did you know /* you can nest multiline comments */ ? */