Hashtag
A hashtag is a word or series of words preceded by a hashtag (#). Example: #marketing terms. Hashtags are used in social media like Twitter to "tag" messages so that they are easier to find through the internal search function. For example, it is possible to track all tweets about a TV broadcast, event or news event.
Hashtags have become familiar to the general public thanks to Twitter. They originated in the IRC chat network. Other social networks, such as Instagram, Facebook and YouTube, also offer features around hashtags in status updates.
