Swift version: 5.0
Double data type is the standard Swift way of storing decimal numbers such as 3.1, 3.14159 and 16777216.333921. Whenever you create a variable or constant that holds a number like this, Swift automatically assumes it's a
Double rather than a
Float, because it has a higher precision and therefore less likely to lose valuable accuracy.
Available from iOS 7.0 – learn more in my book
This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.