That means when someone mistypes a URL or non-existent domain name it will go to Verisign's advertising/search engine site.
So a clearly bogus site (www.marcnozelllikesdebian989283492340.com) will resolve in DNS.
$host www.marcnozelllikesdebian989283492340.com
www.marcnozelllikesdebian989283492340.com has address 64.94.110.11
$