The octothorp — pound sign, number sign, hashtag — first appeared on phones decades ago. Early internet chats used the symbol to connect people and ideas, and the hashtag recently celebrated a 10-year anniversary as a Twitter user suggestion that has spread across social platforms.

As a tool for self-organizing, they can get #annoying. Still, they are very useful for social listening, and you should consider them for the following:

  1. Campaigns — connect people to issues and causes, launches and sales (#optoutside)
  2. Contests — entries are easy to spot when tagged; check the platform rules before launch (#TPDress)
  3. Events — collecting online and offline conversations expands reach, including long tail discovery (#sxsw)
  4. Community — organizing conversation about your brand (#mystarbucksidea #NuggsforCarter)