String interpolation is a way to construct a new String value from a mix of constants, variables, literals, and expressions by including their values inside a string literal. Each item that you insert into the string literal is wrapped in a pair of parentheses, prefixed by a backslash:
- let multiplier = 3
- let message = "\(multiplier) times 2.5 is \(Double(multiplier) * 2.5)"
- // message is "3 times 2.5 is 7.5"