Google+ platform websites integration using the Google+ platform tag.
The Tweet Button is a small widget which allows visitors to share content and connect on Twitter.
Let visitors recommend your content on Google Search and share it on Google+.
A family of standard web feed formats used to publish frequently updated information like blog entries, news headlines, audio and video.
Allows a website to define how a page is rendered in Internet Explorer 8, allowing a website to decide to use IE7 style rendering over IE8 rendering.
Open graph description entity tag
Sites who has this tag are verfied by google to use WebMaster tools