hashtag#Hashtags

File:Chris Messina - South by Southwest 2010 (1).jpg suggested using hashtags on Twitter]]

The number sign or hash symbol, #, has long been used in information technology to highlight specific pieces of text. In 1970, the number sign was used to denote immediate address mode in the assembly language of the PDP-11{{cite web |url=https://programmer209.wordpress.com/2011/08/03/the-pdp-11-assembly-language/ |title=PDP-11 assembly language |publisher=Programmer209.wordpress.com |date=August 3, 2011 |access-date=August 25, 2014}} when placed next to a symbol or a number, and around 1973, '#' was introduced in the C programming language to indicate special keywords that the C preprocessor had to process first.{{cite book |title=The C Programming Language |author1=B. W. Kernighan |author2=D. Ritchie |publisher=Prentice Hall |year=1978 |pages=[https://archive.org/details/cprogramminglang00kern/page/86 86], 207 |isbn=978-0-13-110163-0 |title-link=The C Programming Language}} The pound sign was adopted for use within IRC (Internet Relay Chat) networks around 1988 to label groups and topics."Channel Scope". Section 2.2. {{IETF RFC|2811}} 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 uses an ampersand '&').{{cite IETF |title=Internet Relay Chat Protocol |rfc=1459 |sectionname=Channels |section=1.3 |last1=Oikarinen |first1=Jarkko |author-link1=Jarkko Oikarinen |last2=Reed |first2=Darren |year=1993 |publisher=IETF |access-date=June 3, 2014}}

The use of the pound sign in IRC inspired{{cite web |url=http://www.cmu.edu/homepage/computing/2014/summer/originstory.shtml |title=#OriginStory |publisher=Carnegie Mellon University |date=August 29, 2014}} Chris Messina to propose a similar system on Twitter to tag topics of interest on the microblogging network.{{cite news | url=https://www.nytimes.com/2011/06/12/fashion/hashtags-a-new-way-for-tweets-cultural-studies.html?_r=1&pagewanted=all | title=Twitter's Secret Handshake | work=The New York Times | date=June 10, 2011 | access-date=July 26, 2011 | author=Parker, Ashley}} He proposed the usage of hashtags on Twitter:

{{quote |1=How do you feel about using # (pound) for groups. As in #barcamp [msg]? |author = Chris Messina |source = ("factoryjoe"), August 23, 2007}}

According to Messina, he suggested use of the hashtag to make it easy for lay users without specialized knowledge of search protocols to find specific relevant content. Therefore, the hashtag "was created organically by Twitter users as a way to categorize messages".{{Cite journal |last=Scott |first=Kate |date=May 1, 2015 |title=The pragmatics of hashtags: Inference and conversational style on Twitter |journal=Journal of Pragmatics |volume=81 |pages=8–20 |doi=10.1016/j.pragma.2015.03.015 |url=http://eprints.kingston.ac.uk/31291/1/Scott-K-31291.pdf}}

The first published use of the term "hash tag" was in a blog post "Hash Tags = Twitter Groupings" by Stowe Boyd,{{cite web |url=http://stoweboyd.com/post/39877198249/hash-tags-twitter-groupings |title=Stowe Boyd, Hash Tags = Twitter Groupings |publisher=Stoweboyd.com |access-date=September 19, 2013 |archive-date=September 15, 2013 |archive-url=https://web.archive.org/web/20130915192357/http://stoweboyd.com/post/39877198249/hash-tags-twitter-groupings |url-status=dead }} on August 26, 2007, according to lexicographer Ben Zimmer, chair of the American Dialect Society's New Words Committee.

File:Global Summit to End Sexual Violence in Conflict (14203190979).jpg

Messina's suggestion to use the hashtag was not immediately adopted by Twitter, but the convention gained popular acceptance when hashtags were used in tweets relating to the 2007 San Diego forest fires in Southern California.[http://mashable.com/2013/10/08/what-is-hashtag/ What is hashtag?"] {{Webarchive|url=https://web.archive.org/web/20160425141850/http://mashable.com/2013/10/08/what-is-hashtag/ |date=April 25, 2016 }}, Mashable, 8 October 2013.{{cite web |url=https://factoryjoe.com/2007/10/22/twitter-hashtags-for-emergency-coordination-and-disaster-relief/ |title=Twitter hashtags for emergency coordination and disaster relief |website=Factory Joe |access-date=September 16, 2017 |date=2007-10-23}} The hashtag gained international acceptance during the 2009–2010 Iranian election protests; Twitter users used both English- and Persian-language hashtags in communications during the events.{{cite news |title=The story of the hashtag began with Iranians |url=http://www.dw.de/حکایت-هشتگی-که-ایرانیان-آغاز-کردند/g-18012627 |access-date=March 12, 2015 |publisher=Deutsche Welle Persian |date=2009}}

Hashtags have since played critical roles in recent social movements such as #jesuischarlie, #BLM,{{cite web |url=https://www.theverge.com/2020/6/2/21277852/blackout-tuesday-posts-hiding-information-blm-black-lives-matter-hashtag |title=Blackout Tuesday posts are drowning out vital information shared under the BLM hashtag |first=James |last=Vincent |date=June 2, 2020 |work=The Verge}} and #MeToo.{{Cite web |title=#MeToo and more — five hashtags for equality |date=2019-10-15 |url=https://www.dw.com/en/metoo-and-more-five-hashtags-for-equality/a-50838357 |access-date=2020-09-03 |website=DW.com |language=en-GB}}{{Cite web |last=Brown |first=Dalvin |title=19 million tweets later: A look at #MeToo a year after the hashtag went viral |url=https://www.usatoday.com/story/news/2018/10/13/metoo-impact-hashtag-made-online/1633570002/ |access-date=2020-09-03 |website=USA TODAY |language=en-US}}

Beginning July 2, 2009,{{cite web |title=Twitter Makes Hashtags More #Useful |date=July 2, 2009 |url=https://techcrunch.com/2009/07/02/twitter-makes-hashtags-more-useful/ |access-date=December 27, 2015}} 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, and the significance of trending hashtags has become so great that the company makes significant efforts to foil attempts to spam the trending list.{{cite web |url=http://www.allisayis.com/the-secret-of-twitters-trending-hashtags-with-insight-and-tips/ |title=The Secret of Twitter's Trending Hashtags With Insight and Tips |publisher=AllISayIs.com |access-date=December 3, 2014 |archive-url=https://web.archive.org/web/20150505141532/http://www.allisayis.com/the-secret-of-twitters-trending-hashtags-with-insight-and-tips/ |archive-date=May 5, 2015 |url-status=dead }} During the 2010 World Cup, Twitter explicitly encouraged the use of hashtags with the temporary deployment of "hashflags", which replaced hashtags of three-letter country codes with their respective national flags.{{cite web |url=http://www.ryanseacrest.com/2010/06/11/twitter-supports-world-cup-fever-with-hashflags/ |title=Twitter Supports World Cup Fever with Hashflags |publisher=Ryanseacrest.com |date=June 11, 2010 |access-date=August 5, 2015 |archive-url=https://web.archive.org/web/20101129201517/http://ryanseacrest.com/2010/06/11/twitter-supports-world-cup-fever-with-hashflags/ |archive-date=November 29, 2010}}

Other platforms such as YouTube and Gawker Media followed in officially supporting hashtags,{{cite web |url = http://www.niemanlab.org/2009/10/got-a-tip-gawker-media-opens-tag-pages-to-masses-expecting-chaos/ |title = Got a #tip? Gawker Media opens tag pages to masses, expecting "chaos" |author = Zachary M. Seward |publisher = Nieman Journalism Lab |date = October 15, 2009 }} and real-time search aggregators such as Google Real-Time Search began supporting hashtags.

A hashtag must begin with a hash (#) character followed by other characters, and is terminated by a space or the end of the line. Some platforms may require the # to be preceded with a space. Most or all platforms that support hashtags permit the inclusion of letters (without diacritics), numerals, and underscores.{{r|charset}} Other characters may be supported on a platform-by-platform basis. Some characters, such as "&", are generally not supported as they may already serve other search functions.{{cite web |author=Eden |first=Terence |author-link=Terence Eden |date=25 February 2010 |title=Hashtag Standards |url=https://shkspr.mobi/blog/2010/02/hashtag-standards/ |access-date=21 September 2017 |website=Terence Eden's Blog}} Hashtags are not case sensitive (a search for "#hashtag" will match "#HashTag" as well), but the use of embedded capitals (i.e., CamelCase) increases legibility and improves accessibility.

Languages that do not use word dividers handle hashtags differently. In China, microblogs Sina Weibo and Tencent Weibo use a double-hashtag-delimited #HashName# format, since the lack of spacing between Chinese characters necessitates a closing tag. Twitter uses a different syntax for Chinese characters and orthographies with similar spacing conventions: the hashtag contains unspaced characters, separated from preceding and following text by spaces (e.g., '我 #爱 你' instead of '我#爱你'){{cite news|last1=Martin|first1=Rick|title=Twitter Rolls Out Hashtag Support for Japanese, Korean, Chinese, and Russian|url=https://www.techinasia.com/twitter-hashtag-languages/|access-date=March 5, 2015|publisher=Tech in Asia|date=July 13, 2011}} or by zero-width non-joiner characters before and after the hashtagged element, to retain a linguistically natural appearance (displaying as unspaced '我‌#爱‌你', but with invisible non-joiners delimiting the hashtag).{{cite news|last1=International services team|title=Right-to-left languages on Twitter|url=https://blog.twitter.com/2012/right-to-left-languages-on-twitter|access-date=March 5, 2015|publisher=Twitter|date=April 5, 2012|archive-url=https://web.archive.org/web/20150402172013/https://blog.twitter.com/2012/right-to-left-languages-on-twitter|archive-date=April 2, 2015|url-status=dead|df=mdy-all}}

Some communities may limit, officially or unofficially, the number of hashtags permitted on a single post.{{cite web|title=What is a (#) Hashtag?|url=http://www.hashtags.org/how-to/history/what-is-a-hashtag/|publisher=Hashtags.org|date=24 June 2012|access-date=February 22, 2014}}

Misuse of hashtags can lead to account suspensions. Twitter warns that adding hashtags to unrelated tweets, or repeated use of the same hashtag without adding to a conversation can filter an account from search results, or suspend the account.{{cite web|title=The Twitter Rules|url=https://support.twitter.com/groups/56-policies-violations/topics/236-twitter-rules-policies/articles/18311-the-twitter-rules|publisher=Twitter, Inc.|access-date=September 22, 2017|quote=if you post multiple unrelated updates to a topic using # ...}}

Individual platforms may deactivate certain hashtags either for being too generic to be useful, such as #photography on Instagram, or due to their use to facilitate illegal activities.{{cite news |url=https://www.bbc.co.uk/news/technology-24842750 |title=Instagram banned hashtags | date = November 7, 2013|work=BBC.co.uk |access-date=November 25, 2013}}{{cite journal |last=Olszanowski |first=M. |date=2014 |title=Feminist Self-Imaging and Instagram: Tactics of Circumventing Sensorship{{sic|hide=y}} |journal=Visual Communication Quarterly |volume=21 |issue=1 |pages=83–95 |access-date=February 8, 2015 |url=http://www.tandfonline.com/doi/abs/10.1080/15551393.2014.928154 |url-access=subscription |doi=10.1080/15551393.2014.928154|s2cid=145667227 }}

In 2009, StockTwits began using ticker symbols preceded by the dollar sign (e.g., $XRX).{{cite journal |author=Wong, Matthew |title=VCs and tart-Ups Pin Their Hopes on Pinterest |date=August 17, 2012 |journal=The Wall Street Journal |url=https://blogs.wsj.com/venturecapital/2012/08/17/vcs-and-start-ups-pin-their-hopes-on-pinterest/ |access-date=May 28, 2013 }}{{cite news |last=Taylor |first=Colleen |title=Howard Lindzon on Why He Sold His Twitter Stock, And The 'Hijack' Of StockTwits' Cashtags [TCTV] |date=July 1, 2012 |work=TechCrunch |url=https://techcrunch.com/2012/08/01/howard-lindzon-on-why-he-sold-his-twitter-stock-and-the-hijack-of-stocktwits-cashtags-tctv/ |access-date=May 9, 2013 }} In July 2012, Twitter began supporting the tag convention and dubbed it the "cashtag".{{cite web|last=Kim |first=Erin |url=https://money.cnn.com/2012/07/31/technology/twitter-cashtag/ |title=Twitter unveils 'cashtags' to track stock symbols – Jul. 31, 2012 |publisher=CNN Money |date=July 31, 2012 |access-date=November 12, 2013}}{{cite web|url=https://www.theverge.com/2012/7/30/3205284/twitter-stock-ticker-cashtag-links-official |title=Twitter makes stock symbol $ 'cashtag' links official, following # and @ |website=The Verge |date=July 30, 2012 |access-date=November 12, 2013}} The convention has extended to national currencies, and Cash App has implemented the cashtag to mark usernames.

File:Seguir hashtags.png

Hashtags are particularly useful in unmoderated forums that lack a formal ontological organization. Hashtags help users find content similar interest. Hashtags are neither registered nor controlled by any one user or group of users. They do not contain any set definitions, meaning that a single hashtag can be used for any number of purposes, and that the accepted meaning of a hashtag can change with time.

Hashtags intended for discussion of a particular event tend to use an obscure wording to avoid being caught up with generic conversations on similar subjects, such as a cake festival using #cakefestival rather than simply #cake. However, this can also make it difficult for topics to become "trending topics" because people often use different spelling or words to refer to the same topic. For topics to trend, there must be a consensus, whether silent or stated, that the hashtag refers to that specific topic.

Hashtags may be used informally to express context around a given message, with no intent to categorize the message for later searching, sharing, or other reasons. Hashtags may thus serve as a reflexive meta-commentary.{{Cite journal |last=Wikström |first=Peter |date=2014 |title=#srynotfunny: Communicative Functions of Hashtags on Twitter |url=https://kau.diva-portal.org/smash/get/diva2:779005/FULLTEXT01.pdf |journal=SKY Journal of Linguistics |volume=27 |pages=127–152 |access-date=May 15, 2016}}

This can help express contextual cues or offer more depth to the information or message that appears with the hashtag. "My arms are getting darker by the minute. #toomuchfaketan". Another function of the hashtag can be used to express personal feelings and emotions. For example, with "It's Monday!! #excited #sarcasm" in which the adjectives are directly indicating the emotions of the speaker.{{Cite journal |last=Caleffi |first=Paola-Maria |date=2015 |title=The 'hashtag': A new word or a new rule? |url=http://www.skase.sk/Volumes/JTL28/pdf_doc/05.pdf |journal=Skase Journal of Theoretical Linguistics |volume=12 |issue=2 |issn=1336-782X}}

Verbal use of the word hashtag is sometimes used in informal conversations.{{cite web|url=http://www.macmillandictionary.com/dictionary/british/hashtag|title=hashtag (noun) definition and synonyms|website=Macmillan Dictionary|access-date=September 16, 2017}} Use may be humorous, such as "I'm hashtag confused!" By August 2012, use of a hand gesture, sometimes called the "finger hashtag", in which the index and middle finger both hands are extended and arranged perpendicularly to form the hash, was documented.{{cite web |url=https://www.theguardian.com/technology/shortcuts/2012/aug/01/how-to-say-hashtag-fingers |title=How to say 'hashtag' with your fingers |work=The Guardian |author=Tom Meltzer |date=August 1, 2012 |access-date=March 20, 2014}}{{cite magazine |url=https://www.wired.co.uk/news/archive/2013-03/06/hashtags |title=Finger-Hashtags |magazine=Wired |author=Nimrod Kamer |date=March 2013 |access-date=March 20, 2014|author-link=Nimrod Kamer }}

Companies, businesses, and advocacy organizations have taken advantage of hashtag-based discussions for promotion of their products, services or campaigns.

In the early 2010s, some television broadcasters began to employ hashtags related to programs in digital on-screen graphics, to encourage viewers to participate in a backchannel of discussion via social media prior to, during, or after the program.{{cite magazine|author=Michael Schneider|date=April 21, 2011|title=New to Your TV Screen: Twitter Hashtags|url=http://www.tvguide.com/News/New-TV-Screen-1032111.aspx|magazine=TV Guide}} Television commercials have sometimes contained hashtags for similar purposes.{{cite web|author=Todd Wasserman|date=December 3, 2012|title=McDonald's Releases First TV Ad With Twitter Hashtag|url=http://mashable.com/2012/12/03/mcdonalds-tv-ad-twitter-hashtag/|publisher=Mashable}}

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 television commercials and series episodes.{{cite web|url = https://techcrunch.com/2012/06/10/twitter-hashtag-pages-aol-keywords/|title = Twitter's Hashtag Pages Could Be The New AOL Keywords — But Better|author = Ryan Lawler|date = June 10, 2012|publisher = Techcrunch}}

Organized real-world events have used hashtags and ad hoc lists for discussion and promotion among participants. Hashtags are used as beacons by event participants to find each other, both on Twitter and, in many cases, during actual physical events.

Since the 2012–13 season, the NBA has allowed fans to vote players in as All-Star Game starters on Twitter and Facebook using #NBAVOTE.{{Cite web|url=http://www.nba.com/2013/news/11/15/2014-nba-all-star-ballot-official-release/|title=NBA and Sprint tip off NBA All-Star Balloting 2014|website=NBA.com|date=November 15, 2013}}

Hashtag-centered biomedical Twitter campaigns have shown to increase the reach, promotion, and visibility of healthcare-related open innovation platforms.{{Cite journal|date=2021-01-01|title=Impacts of biomedical hashtag-based Twitter campaign: #DHPSP utilization for promotion of open innovation in digital health, patient safety, and personalized medicine|journal=Current Research in Biotechnology|language=en|volume=3|pages=146–153|doi=10.1016/j.crbiot.2021.04.004|issn=2590-2628|doi-access=free|last1=Kletecka-Pulker|first1=Maria|last2=Mondal|first2=Himel|last3=Wang|first3=Dongdong|last4=Parra|first4=R. Gonzalo|last5=Maigoro|first5=Abdulkadir Yusif|last6=Lee|first6=Soojin|last7=Garg|first7=Tushar|last8=Mulholland|first8=Eoghan J.|last9=Devkota|first9=Hari Prasad|last10=Konwar|first10=Bikramjit|last11=Patnaik|first11=Sourav S.|last12=Lordan|first12=Ronan|last13=Nawaz|first13=Faisal A.|last14=Tsagkaris|first14=Christos|last15=Rayan|first15=Rehab A.|last16=Louka|first16=Anna Maria|last17=De|first17=Ronita|last18=Badhe|first18=Pravin|last19=Schaden|first19=Eva|last20=Willschke|first20=Harald|last21=Maleczek|first21=Mathias|last22=Boyina|first22=Hemanth Kumar|last23=Khalid|first23=Garba M.|last24=Uddin|first24=Md. Sahab|last25=Sanusi|last26=Khan|first26=Johra|last27=Odimegwu|first27=Joy I.|last28=Yeung|first28=Andy Wai Kan|last29=Akram|first29=Faizan|last30=Sai|first30=Chandragiri Siva|display-authors=1|hdl=1805/29874|hdl-access=free}}

File:Occupy for Rights.JPG promoting the hashtag #OccupyForRights]]

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 frequently employed to either show support or opposition towards political figures. For example, the hashtag #MakeAmericaGreatAgain signifies support for Trump, whereas #DisinfectantDonnie expresses ridicule of Trump.{{Cite journal |last=Wan |first=Ming Feng |date=2024-03-12 |title=The role of syntax in hashtag popularity |url=https://www.degruyter.com/document/doi/10.1515/lingvan-2023-0051/html |journal=Linguistics Vanguard |language=en |volume=10 |issue=1 |pages=693–698 |doi=10.1515/lingvan-2023-0051 |issn=2199-174X|url-access=subscription }} Hashtags have also been used to promote official events; the Finnish Ministry of Foreign Affairs officially titled the 2018 Russia–United States summit as the "#HELSINKI2018 Meeting".{{Cite web|url=https://um.fi/helsinki2018|title=#HELSINKI2018 - Ministry for Foreign Affairs|website=um.fi|access-date=2018-07-11|archive-date=July 10, 2018|archive-url=https://web.archive.org/web/20180710075902/https://um.fi/helsinki2018|url-status=dead}}

Hashtags have been used to gather customer criticism of large companies. In January 2012, McDonald's created the #McDStories hashtag so that customers could share positive experiences about the restaurant chain, but the marketing effort was cancelled after two hours when critical tweets outnumbered praising ones.{{cite news | first = Alexis | last = Akwagyiram | title = Are Twitter and Facebook changing the way we complain? | date = May 17, 2012 | url = https://www.bbc.co.uk/news/uk-18081651 | work = BBC News | access-date = June 12, 2012}}

File:The rise of hashtag activism.jpg

In 2017, the #MeToo hashtag became viral in response to the sexual harassment accusations against Harvey Weinstein. The use of this hashtag can be considered part of hashtag activism, spreading awareness across eighty-five different countries with more than seventeen million Tweets using the hashtag #MeToo. This hashtag was not only used to spread awareness of accusations regarding Harvey Weinstein but allowed different women to share their experiences of sexual violence. Using this hashtag birthed multiple different hashtags in connection to #MeToo to encourage more women to share their stories, resulting in further spread of the phenomenon of hashtag activism. The use of hashtags, especially, in this case, allowed for better and easier access to search for content related to this social media movement.{{Cite journal |last=Lindgren |first=Simon |date=2019-07-29 |title=Movement Mobilization in the Age of Hashtag Activism: Examining the Challenge of Noise, Hate, and Disengagement in the #MeToo Campaign |url=https://onlinelibrary.wiley.com/doi/abs/10.1002/poi3.212 |journal=Policy & Internet |volume=11 |issue=4 |pages=418–438 |doi=10.1002/poi3.212 |issn=1944-2866 |s2cid=201423139|url-access=subscription }}

The use of hashtags also reveals what feelings or sentiment an author attaches to a statement. This can range from the obvious, where a hashtag directly describes the state of mind, to the less obvious. For example, words in hashtags are the strongest predictor of whether or not a statement is sarcastic{{cite journal|last=Maynard|title=Who cares about sarcastic tweets? Investigating the impact of sarcasm on sentiment analysis|journal=Proceedings of the Conference on Language Resources and Evaluation|year=2014}}—a difficult AI problem.{{cite web|url=http://www.huffingtonpost.com/entry/power-yourself-with-viral-marketing-become-a-hashtag_us_57bf13e6e4b06384eb3e7f1d?dxrywr9zcw30rizfr |title=Power yourself with viral marketing - become a HashTag Genius |website=huffingtonpost.com|date=August 25, 2016 |access-date=September 16, 2017}}

Hashtags play an important role for employees and students in professional fields and education. In industry, individuals' engagement with a hashtags can provide opportunities for them develop and gain some professional knowledge in their fields.{{Cite journal|last=Veletsianos|first=George|date=2017|title=Three Cases of Hashtags Used as Learning and Professional Development Environments|url=https://link.springer.com/content/pdf/10.1007/s11528-016-0143-3.pdf|journal=TechTrends|volume=61|issue=3|pages=284–292|doi=10.1007/s11528-016-0143-3|s2cid=64476519}}

In education, research on language teachers who engaged in the #MFLtwitterati hashtag demonstrates the uses of hashtags for creating community and sharing teaching resources. The majority of participants reported positive impact on their teaching strategies as inspired by many ideas shared by different individuals in the Hashtag.{{Cite journal|last=Rosell-Aguilar|first=Fernando|date=2018|title=Twitter: A Professional Development and Community of Practice Tool for Teachers|url=https://oro.open.ac.uk/54356/9/452-3655-1-PB.pdf|journal=Journal of Interactive Media in Education|volume=6}}

Emerging research in communication and learning demonstrates how hashtag practices influence the teaching and development of students. An analysis of eight studies examined the use of hashtags in K–12 classrooms and found significant results. These results indicated that hashtags assisted students in voicing their opinions. In addition, hashtags also helped students understand self-organisation and the concept of space beyond place. {{clarify|date=April 2021}}{{Cite journal|last=Ellen|first=Watson|date=2020|title=Education: The Potential Impact of Social Media and Hashtag Ideology on the Classroom. Research in Social Sciences and Technology|url=https://ressat.org/index.php/ressat/article/view/390|journal=Research in Social Sciences and Technology|volume=5|pages=40–56|doi=10.46303/ressat.05.02.3|doi-access=free}} Related research demonstrated how high school students engagement with hashtag communication practices allowed them to develop story telling skills and cultural awareness.{{Cite journal|last=Gleason|first=Benjamin|date=2018|title=Thinking in hashtags: exploring teenagers' new literacies practices on Twitter|url=https://lib.dr.iastate.edu/cgi/viewcontent.cgi?article=1098&context=edu_pubs|journal=Learning, Media and Technology|volume=43|issue=2|pages=165–180|doi=10.1080/17439884.2018.1462207|s2cid=64826675}}

For young people at risk of poverty and social exclusion during the COVID-19 pandemic, Instagram hashtags were shown in a 2022 article to foster scientific education and promote remote learning.{{Cite journal |last1=Puigvert |first1=Lídia |last2=Villarejo-Carballido |first2=Beatriz |last3=Gairal-Casadó |first3=Regina |last4=Gómez |first4=Aitor |last5=Cañaveras |first5=Paula |last6=Martí |first6=Teresa Sordé |date=2022-02-10 |title=An Instagram Hashtag Fostering Science Education of Vulnerable Groups during the Pandemic |journal=International Journal of Environmental Research and Public Health |language=en |volume=19 |issue=4 |pages=1974 |doi=10.3390/ijerph19041974 |issn=1660-4601 |pmc=8872541 |pmid=35206162|doi-access=free }}

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During the April 2011 Canadian party leader debate, Jack Layton, then-leader of the New Democratic Party, referred to Conservative Prime Minister Stephen Harper's crime policies as "{{sic|a}} hashtag fail" (presumably #fail).{{cite news|url = https://www.theglobeandmail.com/news/politics/jack-laytons-debatable-hashtag-fail/article576224/|title = Jack Layton's debatable 'hashtag' #fail|author = Anna Mehler Paperny|newspaper = The Globe and Mail|date = April 13, 2011 }}{{cite news|url = https://www.cbc.ca/news/politics/canadians-atwitter-throughout-debate-1.1028325|title = Canadians atwitter throughout debate|date = April 13, 2011|publisher = CBC News}}

In 2010 Kanye West used the term "hashtag rap" to describe a style of rapping that, according to Rizoh of the Houston Press, uses "a metaphor, a pause, and a one-word punch line, often placed at the end of a rhyme".{{cite news|url = http://blogs.villagevoice.com/music/2010/11/the_ten_best_qu.php|title = The Ten Best Quotes From Kanye West's Epic Hot 97 Interview With Funkmaster Flex|author = Zach Baron|newspaper = The Village Voice|date = November 3, 2010|access-date = July 22, 2013|archive-url = https://web.archive.org/web/20130722084923/http://blogs.villagevoice.com/music/2010/11/the_ten_best_qu.php|archive-date = July 22, 2013|url-status = dead|df = mdy-all}}{{cite news|url = http://blogs.houstonpress.com/rocks/2011/07/a_brief_history_of_hashtag_rap.php|title = A Brief History Of Hashtag Rap|author = Rizoh|newspaper = Houston Press|date = July 7, 2011 |access-date = July 22, 2013|archive-date = June 26, 2012|archive-url = https://web.archive.org/web/20120626000742/http://blogs.houstonpress.com/rocks/2011/07/a_brief_history_of_hashtag_rap.php|url-status = dead}} Rappers Nicki Minaj, Big Sean, Drake, and Lil Wayne are credited with the popularization of hashtag rap, while the style has been criticized by Ludacris, The Lonely Island,{{cite web|url = http://www.tucsonweekly.com/TheRange/archives/2013/05/22/the-lonely-island-puts-hashtag-rap-in-its-place-looking-at-you-drake|title = The Lonely Island Puts Hashtag Rap In Its Place (Looking at You, Drake)|author = David Mendez|date = May 22, 2013 |publisher = Tucson Weekly}} and various music writers.{{cite news|url = http://www.joplinglobe.com/enjoy/x1666506743/Jeremiah-Tucker-Hashtag-rap-is-2010s-lamest-trend|title = Jeremiah Tucker: Hashtag rap is 2010's lamest trend|author = Jeremiah Tucker|date = December 17, 2010|newspaper = Joplin Globe}}

On September 13, 2013, a hashtag, #TwitterIPO, appeared in the headline of a New York Times front-page article regarding Twitter's initial public offering.{{cite web | title = A Short Post, a Big Splash: #TwitterIPO | url = https://dealbook.nytimes.com/2013/09/12/twitter-confidentially-submits-plans-for-i-p-o/ | date = September 12, 2013 | last1 = Goel | first1 = Vindu | last2 = Bilton | first2 = Nick | last3 = Gelles | first3 = David | work = The New York Times | access-date = January 19, 2019 }}

{{cite tweet | user = nickbilton | last = Bilton | first = Nick | title = My first byline on A1 of the ... | number = 378534272962793472 | date = September 14, 2013 | access-date = September 14, 2013}}{{dead link|date=January 2019}}

In 2014 Bird's Eye foods released "Mashtags", a mashed potato product with pieces shaped either like

{{char|@}} or {{char|#}}.{{cite web|title=Birds Eye launches Mashtags – social media potato shapes|url=http://www.thegrocer.co.uk/fmcg/birds-eye-launches-mashtags-potato-shapes/354514.article|work=The Grocer}}

In 2019, the British Ornithological Union included a hash character in the design of its new Janet Kear Union Medal, to represent "science communication and social media".{{cite tweet |user=IBIS_journal |number=1133687894831505408 |date=29 May 2019 |title=Our new medal has been designed by our own @stevedudley_ who has a background in design. It [...] uses icons of birds and other #ornithology-related items including people and tech}} [see attached image for explanation of the hash character]

Linguists argue that hashtagging is a morphological process and that hashtags function as words.{{Cite journal |last1=Calude |first1=Andreea S. |last2=Long |first2=Maebh |last3=Burnette |first3=Jessie |date=2024-06-07 |title=#AreHashtagsWords? Structure, position, and syntactic integration of hashtags in (English) tweets |url=https://www.degruyter.com/document/doi/10.1515/lingvan-2023-0044/html |journal=Linguistics Vanguard |language=en |volume=10 |issue=1 |pages=105–114 |doi=10.1515/lingvan-2023-0044 |issn=2199-174X|url-access=subscription }}

The popularity of a hashtag is influenced less by its conciseness and clarity, and more by the presence of preexisting popular hashtags with similar syntactic formats. This suggests that, similar to word formation, users may see the syntax of an existing viral hashtag as a blueprint for creating new ones. For instance, the viral hashtag #JeSuisCharlie gave rise to other popular indicative mood hashtags like #JeVoteMacron and #JeChoisisMarine.

• URI fragment
• Tagging
• Mentioning a user's profile by using @ tagging in blogging.
• Webring, an early-web decentralized mechanism to link websites with a common theme
• Folksonomy
• Social bookmarking
• Models of collaborative tagging
• Web 2.0

{{Reflist|30em}}

{{Commons category|Hashtags}}

• [https://tools.wmflabs.org/hashtags/search/artandfeminism Wikipedia internal hashtag search engine] – for hashtags used in edit summaries
• Veszelszki, Ágnes 2016: [https://www.academia.edu/30714144/Veszelszki_%C3%81gnes_2016_time_truth_tradition._An_image-text_relationship_on_Instagram_photo_and_hashtag._In_Benedek_Andr%C3%A1s_Veszelszki_%C3%81gnes_eds._In_the_Beginning_was_the_Image_The_Omnipresence_of_Pictures_Time_Truth_Tradition._Frankfurt_am_Main_Peter_Lang_139-150 #time, #truth, #tradition. An Image-text Relationship on Instagram: photo and hashtag]. In: Benedek, András; Veszelszki, Ágnes (eds.): In the Beginning was the Image: The Omnipresence of Pictures: Time, Truth, Tradition. Frankfurt am Main: Peter Lang GmbH, Internationaler Verlag der Wissenschaften, pp. 139–150.
• [https://www.stateofdigital.com/the-history-of-the-hashtag/ Infografika Hluboká Historie hashtagu] {{Webarchive|url=https://web.archive.org/web/20220207101936/https://www.stateofdigital.com/the-history-of-the-hashtag/ |date=February 7, 2022 }}
• [https://venngage.com/gallery/post/the-history-of-hashtags/ Infografika Historie hashtagu]
• [https://diff.wikimedia.org/2016/03/23/hashtags-expanding-outreach-wikipedia/ Growing hashtags: Expanding outreach on Wikipedia]
• [https://hashtags.wmcloud.org/docs/ Wikimedia hashtag search]

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Category:2010s slang

Category:Collective intelligence

Category:Computer jargon

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Category:Cultural trends