Splash pages are a one page web build that is extremely simple just a header, a link and some content that is relative to the seo site. The seo site is linked to the splash and the splash is linked to the original. The reason for the splash is because the original is badly seo'ed that it will kill the rankings for the seo site. So the splash site is placed in there as a shield to protect the seo site and allow it to have good rankings, without getting effected by the original. For and example of a SEO site click here http://herbalsite.info/ and the splash that protects it is http://herbalsite.net.