When and why is forced unwrapping of an optional used in Swift?

Force unwrapping an optional in Swift is used when you are sure that the optional contains a value and you want to access that value directly. This is done using the "!" operator after the variable.

Use it with caution, as if the optional turns out to be nil, the application will crash with a runtime error.

Example:

let optionalString: String? = "Hello"
let forcedString: String = optionalString! // safe because optionalString is not nil

Use force unwrapping when you guarantee that the value is not nil, for example, after a check or in places where nil cannot occur.