Hashtag

A hashtag is a metadata tag that is preceded by the hash symbol, #, and is used to identify content on the internet. As a kind of user-generated tagging on microblogging and photo-sharing sites like as Twitter, Instagram, and WeChat, hashtags are used to allow material to be cross-referenced; that is, to share information about a certain subject or theme. Using the hashtag #bluesky, for example, a search inside Instagram reveals all of the posts that have been tagged with that hashtag. After the first hash symbol, a hashtag may include any combination of characters, numerals, and dashes.

Chris Messina, an American blogger, product consultant, and public speaker, was the first to suggest the usage of hashtags in a tweet back in 2007. Messina made no effort to patent the usage since, in his opinion, "they were born of the internet, and are not owned by anybody." According to reports in the Wall Street Journal from 2013, Twitter said that "these things are for geeks" and that their usage "wouldn't be embraced extensively." Although hashtags didn't become widely used until the end of the decade, they quickly became popular on social media platforms such as Instagram, Facebook, and YouTube, where they quickly spread. Added to the Oxford English Dictionary in June 2014, the term hashtag is defined as "a word or phrase with the sign # in front of it, "used on social media websites and applications to allow you to search for all posts with the same topic."