Lightbox and dynamic links - how and why does this work?

I had a problem, was going to ask how to fix it, but then the answer popped up in a related question. Seeing I have little experience with jQuery, I would like to understand exactly "what" happens with what I'm doing.

FYI: jQuery (latest) + jCarousel + Lightbox.

jCarousel creates a few links for me, and Lightbox captures these links and shows a nice frame around the picture I linked.

The code that did the trick was

$('a.gallery').live("click", function(e) {

    $(this).lightBox({

        imageLoading : 'img/lightbox-ico-loading.gif',

        imageBtnClose : 'img/lightbox-btn-close.gif',

        imageBtnPrev : 'img/lightbox-btn-prev.gif',

        imageBtnNext : 'img/lightbox-btn-next.gif'

    });

    $(this).triggerHandler('click');

    e.preventDefault();

});

..instead of

$('a.gallery').lightBox({

    imageLoading : 'img/lightbox-ico-loading.gif',

    imageBtnClose : 'img/lightbox-btn-close.gif',

    imageBtnPrev : 'img/lightbox-btn-prev.gif',

    imageBtnNext : 'img/lightbox-btn-next.gif'

});

My question is; what is the exact difference between these?

Thanks alot