A blog is a discussion or informational site published on the World Wide Web and consisting of discrete posts typically displayed in reverse chronological order (the most recent post appears first). Until 2009 blogs were usually the work of a single individual occasionally of a small group, and often covered a single subject.
Many blogs provide commentary on a particular subject; others function as more personal online diaries; others function more as online brand advertising of a particular individual or company. A typical blog combines text, images, and links to other blogs, Web pages, and other media related to its topic. On 16 February 2011 there were over 156 million public blogs in existence and on 20 February 2014 there were around 75.8 million WordPress blogs in existence worldwide.