With the advent of jQuery the Modal Popups have become much easier. That said, earlier we had some flash pages too. The sole purpose of these as mentioned above is to grab a visitors attention, but then, today, webmasters have come up with better ideas and display messages and special offers on such popups or even the so called splash pages - like maybe - download a free ebook or even buy a service or product for a discounted price. Some also collect emails from their visitors