Great work! By using optionals, you can make sure to handle values that might be nil. A value might be nil because the user didn’t provide a response. A value might also be nil because we might not have a good answer to a question (e.g. what’s the biggest number in an empty list).

In this lesson you learned how to:

• Define optionals
• Force unwrap optionals using the ! operator
• Bind optionals using if let statements
• Bind optionals using guard statements
• Use the nil-coalescing operator ?? to provide default values
• Chain optionals using the ? operator
• Define functions that take in and return optionals

Optionals are anything but optional for writing great Swift code!