Hash ligature (left) written by Isaac Newton compared with a modern-day hash symbol (right) The original ligature stood for libra pondo, or “pound in weight,” which eventually evolved into the # symbol. (more) hashtag label Ask the Chatbot a Question Ask the Chatbot a Question Written by Laura Payne Laura Payne is a freelance writer whose work covers many topics. She is a former Wayne State University linguistics instructor. Laura Payne Fact-checked by The Editors of Encyclopaedia Britannica Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors. The Editors of Encyclopaedia Britannica Last Updated: Nov 19, 2024 • Article History Table of Contents Table of Contents Ask the Chatbot a Question { "@context": "https://schema.org", "@type": "FAQPage", "mainEntity": [ { "@type" : "Question", "name" : " What is a hashtag, and why is it used? ", "acceptedAnswer" : { "@type" : "Answer", "text" : "A hashtag is a metadata label prefaced by the hash symbol (#) and followed by a word or phrase without spaces or special characters. It categorizes and organizes related content on social media, helping users discover topics of interest." } } , { "@type" : "Question", "name" : " How did the hash symbol evolve over time? ", "acceptedAnswer" : { "@type" : "Answer", "text" : "The hash symbol originated from the Roman abbreviation lb for libra pondo (u201Cpound in weightu201D). Over time, it evolved into the # symbol, known as an octothorpe or pound sign, and appeared on typewriters and touch-tone telephones." } } , { "@type" : "Question", "name" : " Who proposed using hashtags on Twitter and when? ", "acceptedAnswer" : { "@type" : "Answer", "text" : "Chris Messina proposed using hashtags on Twitter (now X) in 2007, inspired by their use in Internet Relay Chat to organize chat rooms. He suggested using the hash symbol to group related topics, which eventually led to the widespread adoption of hashtags on social media." } } , { "@type" : "Question", "name" : " What are some examples of hashtag activism? ", "acceptedAnswer" : { "@type" : "Answer", "text" : "Examples of hashtag activism include #BlackLivesMatter, which protests police violence against Black people, and #MeToo, which supports survivors of sexual harassment and assault. Both hashtags promoted social movements and increased awareness of these issues." } } , { "@type" : "Question", "name" : " How have hashtags been used in marketing campaigns? ", "acceptedAnswer" : { "@type" : "Answer", "text" : "Hashtags in marketing include Calvin Kleinu2019s #MyCalvins, which encouraged users to post photos in their Calvin Klein underwear; Red Bullu2019s #PutACanOnIt, which promoted creative photos with a Red Bull can; and Expediau2019s #ThrowMeBack campaign, which called for users to post nostalgic photos for a chance to win a travel voucher." } } ] } Top Questions What is a hashtag, and why is it used? A hashtag is a metadata label prefaced by the hash symbol (#) and followed by a word or phrase without spaces or special characters. It categorizes and organizes related content on social media, helping users discover topics of interest.

　　How did the hash symbol evolve over time? The hash symbol originated from the Roman abbreviation lb for libra pondo (“pound in weight”). Over time, it evolved into the # symbol, known as an octothorpe or pound sign, and appeared on typewriters and touch-tone telephones.

　　Who proposed using hashtags on Twitter and when? Chris Messina proposed using hashtags on Twitter (now X) in 2007, inspired by their use in Internet Relay Chat to organize chat rooms. He suggested using the hash symbol to group related topics, which eventually led to the widespread adoption of hashtags on social media.

　　What are some examples of hashtag activism? Examples of hashtag activism include #BlackLivesMatter, which protests police violence against Black people, and #MeToo, which supports survivors of sexual harassment and assault. Both hashtags promoted social movements and increased awareness of these issues.

　　How have hashtags been used in marketing campaigns? Hashtags in marketing include Calvin Klein’s #MyCalvins, which encouraged users to post photos in their Calvin Klein underwear; Red Bull’s #PutACanOnIt, which promoted creative photos with a Red Bull can; and Expedia’s #ThrowMeBack campaign, which called for users to post nostalgic photos for a chance to win a travel voucher.

　　hashtag, metadata label prefaced by the hash symbol (#) and followed by a word or phrase devoid of spaces, special characters, or punctuation. Hashtags are used on social media platforms to categorize and organize related content, which helps users easily discover topics of interest. After a hashtag is posted, it becomes a hyperlink that leads to related content. For example, if someone searches for #birdwatching, the platform returns any posts that have been tagged with the term. Initially popularized on Twitter (now X), hashtags are now used on almost every major social media platform, including LinkedIn, Instagram, TikTok, YouTube, Facebook, ...(100 of 1307 words)

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