title: Continuous or infinite scrolling, more content load when nearing page bottom
body: <p>I've been asked to design a site that continuously expands as the user keeps scrolling. Im experienced in JavaScript but I've never came across anything that could manage this. Popular sites that use this technique are Twitter and Facebook. I know that I'm going to need AJAX to load more content but I'm unsure as to how the browser will know that the user is nearing the bottom of the page?</p>