Technically, it's not recursion. It calls the same function
(showNextImage), but at a later time. It doesn't really call itself
(recursion) because it's the anonymous callback function passed to
fadeIn()
that is calling
showNextImage()
as each one completes.
FadeIn() accepts a
callback function. The callback function is called when the fade has completed.
You should make sure you learn about callback functions, because
they are central and essential to jQuery, and, indeed, any non-trivial
Javascript programming. And you've almost certainly already used them!