Hashtag (#) is currently used in digital media to signify tags that contain content and media related to specific groups, keywords or events.
Hashtag became a term that came to popular use on social media website Twitter. The pound (#) symbol found on classic flip phones was now being used to start topics beginning with #, now called a hashtag followed by a title. The title would then act as a link to 140 character limited tweets relating to the hashtag. For example, a tag such as #collegelife would be a hashtag topic filled with tweets by college students who talk about everything from assignment websites to late night drinking to pizza delivery to classrooms. Twitter users can even follow the hashtag #collegelife and have it show up in their personalized Twitter feed.
The hashtag's origins reach even farther back to IRC (Internet Relay Chat) where hashtags (#) were used to group posts relating to specific topics. Twitter user and IRC user @factoryjoe (Chris Messina) first suggested the use of the hashtag to link to groupings through a tweet, and later expanded his idea for the concept in a blog post on Aug 25, 2007. In 2015, the hashtag is widely used and accepted on Twitter and has expanded to sites like Tumblr and Instagram, where users can find content tagged with the #topic they're looking for.
Popular Culture Edit
#selfie, pronounced "hashtag selfie". A selfie is a photograph that one takes of oneself, for sharing on a social media site. It is a popular tag on Instagram. Selfie was a show by ABC that featured a female lead who is popular on social media, with her selfies garnering tons of 'likes' by users who appreciated her self portraits. The plot focuses on a media guru helping her self image in the real world, and is a commentary on social media and interpersonal connections in contemporary life. 
The hashtag has also been used in activism on social media. For example #IceBucketChallenge was used for a campaign to raise funds for ALS(Amyotrophic lateral sclerosis) research and support for people with ALS. On Twitter and social media, tweets and posts related to the Ice Bucket Challenge were easily accessed using the hashtag.
Hashtags have been picked up by companies for advertisement campaigns as well. Coca-cola did a #shareacoke campaign where coke bottle had names on them rather than the company to promote people to share cokes to people with their names on the bottle. 
Readings and Resources
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