X The Hashtag (2007)
Chris Messina proposed the hashtag; Twitter later adopted it.
DateAug 23, 2007
PlatformX (Twitter)
TypeFeature
Who it affectsEveryone
What happened
Chris Messina proposed using the # symbol to group conversations on Twitter in August 2007. Twitter later turned hashtags into clickable links and trending topics.
Who it affected
Everyone.
What it means for marketers today
Hashtags spread to every social platform. Today a few relevant hashtags help more than many generic ones.
Related
See the full X (Twitter) History: Every Major Change (2006–2026)