Hovercards enhance plain Gravatar images with information about a person: name, bio, pictures, their contact info, and other services.
Earlier this services is provide by only in WordPress.com users but it is now officially available for self hosted WordPress blog,through Jet Pack Plugin.
WordPress is web software you can use to create a beautiful website or blog. We like to say that WordPress is both free and priceless at the same time.
SEO is an acronym for “search engine optimization” or “search engine optimizer.”
According to Wikipedia
Search engine optimization (SEO) is the process of improving the visibility of a website or a web page in search engines via the “natural” or un-paid (“organic” or “algorithmic”) search results.
Web site owners use the /robots.txt file to give instructions about their site to web robots; this is called The Robots Exclusion Protocol.