A hashtag is a word or an unspaced phrase prefixed with the hash character (or number sign), #, to form a label. It is a type of metadata tag. Words or phrases in messages on microblogging and social networking services such as Facebook, Google+, Instagram, Twitter, or VK may be tagged by entering # before them, either as they appear in a sentence, e.g., “New artists announced for #SXSW2014 Music Festival” or appended to it. The term hashtag can also refer to the hash symbol itself when used in the context of a hashtag. A hashtag allows grouping of similarly tagged messages, and also allows an electronic search to return all messages that contain it. Due to its widespread use, ‘hashtag’ was added to the Oxford English Dictionary in June 2014.