A hashtag is a word or a phrase prefixed with the hash symbol: #. It is a form of metadata tag, for example, short messages on microblogging and social networking services such as Twitter or Instagram may be tagged by putting ‘#’ before important words, either as they appear in a sentence, or appended to it.
Hashtags provide a means of grouping such messages, since one can search for the hashtag and get the set of messages that contain it.
Hashtags first appeared and were used within IRC (Internet Relay Chat, a protocol created in 1988) to label groups and topics, and to mark individual messages as belonging to a particular ‘channel.’ Generally, channels or topics that are available across an entire IRC network are prefixed with a hash symbol # (as opposed to those local to a server, which use an ampersand ‘&’). This usage inspired then Google software engineer Chris Messina to propose a similar system to be used on Twitter. He posted the first hashtag on Twitter: ‘how do you feel about using # (pound) for groups. As in #barcamp [msg]?’ in 2007.
Internationally, the hashtag came to prominence during the 2009–2010 Iranian election protests, as both English and Persian-language hashtags became useful for Twitter users inside and outside of Iran. Beginning in 2009, Twitter began to hyperlink all hashtags in tweets to Twitter search results for the hashtagged word (and for the standard spelling of commonly misspelled words). In 2010, Twitter introduced ‘Trending Topics’ on the Twitter front page, displaying hashtags that are rapidly becoming popular.
Hashtags are mostly used as unmoderated ad hoc discussion forums; any combination of characters led by a hash symbol is a hashtag, and any hashtag, if promoted by enough individuals, can ‘trend’ and attract more individual users to discussion using the hashtag. Hashtags are neither registered nor controlled by any one user or group of users, and neither can they be ‘retired’ from public usage, meaning that hashtags can be used in theoretical perpetuity depending upon the longevity of the word or set of characters in a written language. They also do not contain any set definitions, meaning that a single hashtag can be used for any number of purposes as espoused by those who make use of them.
Hashtags can be used on the social network Instagram, by posting pictures and hashtagging it with its subject. As an example, a photo of oneself and a friend posted to the social network can be hashtagged ‘#bffl’ or ‘#friends.’ Hashtags are also used informally to express context around a given message, with no intent to actually categorize the message for later searching, sharing, or other reasons. This can help express humor, excitement, sadness or other contextual cues, for example, ‘Just found out my mom is my health teacher. #awkward’ or ‘It’s Monday!! #excited #sarcasm’. One phenomenon specific to the Twitter system are ‘micro-memes,’ which are emergent topics for which a hashtag is created, used widely for a few days, then disappear. These hashtags also show up in a number of trending topics websites, including Twitter’s own front page.
The hashtag phenomenon has also been harvested for advertisement, promotion and contingency coordination. Most larger organizations will only focus on one or a small number of hashtags. However some individuals and organizations use a large number of hashtags to emphasize the broad range of concepts in which they are interested. Since 2010, television series on various television channels promote themselves through ‘branded’ hashtag bugs (on screen ads). This is used as a means of promoting a backchannel of online side-discussion before, during and after an episode broadcast. Hashtag bugs appear on either corner of the screen, or they may appear at the end of an advertisement.
Personalities associated with broadcasts, such as hosts and correspondents, also promote their corporate or personal Twitter usernames in order to receive mentions and replies to posts; usage of related or ‘branded’ hashtags alongside is increasingly encouraged as a microblogging style in order to ‘trend’ the topic. Chloe Sladden, Twitter’s director of media partnerships, identified two types of television-formatted usage of hashtags: hashtags which identify a series being broadcast (i.e. ‘#SunnyFX’) and instantaneous, ‘temporary’ hashtags issued by television personalities to gauge topical responses from viewers during broadcasts. Some have speculated that hashtags might take the place of (or co-exist) with the Nielsen television ratings system.
The increased usage of hashtags as brand promotion devices has been compared to the promotion of branded ‘keywords’ by AOL in the late 1990s and early 2000s, as such keywords were also promoted at the end of commercials and series episodes.
Organized real-world events have also made use of hashtags and ad hoc lists for discussion and promotion among participants. Hashtags are used as beacons by event participants in order to find each other on both Twitter and, in many cases, in real life during events. Political protests and campaigns in the early 2010s, such as #OccupyWallStreet and #LibyaFeb17, have been organized around hashtags or have made extensive usage of hashtags for the promotion of discussion.
Hashtags are also often used by consumers on social media platforms in order to complain about customer service experiences with large companies. The term ‘bashtag’ has been created to describe situations in which a corporate social media hashtag is used to criticize the company or to tell others about poor customer service. For example, in 2012, McDonald’s created the ‘#McDStories’ hashtag so customers could share positive experiences about the restaurant chain. The marketing effort was cancelled after just two hours when McDonald’s received numerous complaint tweets rather than the positive stories they were expecting.
The term ‘hashtag rap,’ coined by Kanye West, was developed in the 2010s to describe a style of rapping which, according to Rizoh of ‘Houston Press,’ uses ‘three main ingredients: a metaphor, a pause, and a one-word punchline, often placed at the end of a rhyme.’ Rappers Nicki Minaj, Big Sean, Drake and Lil Wayne are credited with the popularization of the genre, while the style has been criticized by Ludacris, The Lonely Island, and various music writers.