Remember the days when you could click on a link and then your web browser would load a new HTML page? Now, clicking on the web will “slide in” something new or run impressive animation to expand a small rectangle into a larger rectangle. You’re still on the same web page, but it seems like most everything is now changed. In fact, you’re no longer clicking, you’re swiping.. and things are flying by fast.
A developer might refer to this as an AJAX-based site. These sites are visually amazing and technically much smarter from a performance and usability standpoint. However, they present challenges to the marketer’s tag-based world where most tags were originally designed with the old before-AJAX mindset.