Google site links for non-branded keywords
Some of you might have noticed that certain websites which rank number one for a specific keyword or search phrase display now below meta description additional set of site links. Please have a look at ranking for “bikes” for www.halfords.com website.
You will notice that site links will change depending on the search phrase eg “bikes” triggers different selection that “kids bikes“. Site links basically list other number 1 ranked pages (in most cases) and are triggered by consistent and high quality ethical optimization across your entire site.
What you can see is the direct result of Google’s determining that a website in general has become a truly authoritative web site from an optimization perspective for a certain subject. In practice the more pages are well optimized and consistently come up in high positions in search results for their own unique keyword phrases, the more likely those additional pages will be linked below website’s primary listing for a particular phrase.
Google attempts this way to help people doing a search to be able to access deeper and more targeted pages also related to the primary search phrase.