Hashtags with Octothorpes

An octothorpe is a distributed hashtag. When you octothorpe a webpage, like this: demo, you link that page to that tag as a concept. This links you to any other page on any other site or app that uses the same octothorpe. This works exactly like a hashtag on a closed platform, except the index lives on an OP server rather than inside a single app. Any site registered with that server can participate, different servers can even federate or combine their hashtag lists.

For more, see the documentation for adding octothorpes to your page