Explain what the term 'Escaping closure' means in the context of Swift programming.

In Swift, the term "Escaping closure" refers to a closure that can be called after the function it was passed to has already finished executing. By default, closures are considered non-escaping, meaning they are called within the body of the function and are not stored for later use.

Escaping closures are used, for example, in asynchronous operations, where the closure is stored and called later, such as after a network request completes.

To indicate such a closure in a function's parameters, the keyword @escaping is used:

func performAsyncOperation(completion: @escaping () -> Void) {
    DispatchQueue.global().async {
        // some work
        completion() // call the closure after the work is done
    }
}

Without @escaping, the compiler will not allow storing the closure for a call after the function exits, to avoid potential issues with memory and object lifecycle.