A hashtag is a type of keyword, in which a word or phrase is marked with a hash (#). With such a hashtag it is possible to search for specific terms by linking thematically overlapping contributions.
This keyword has become known through the microblogging service Twitter. Here it is customary to refer to a specific topic by means of a hashtag. By using specific hashtags
in responses and re-tweets, certain terms become established and are used, for example, in a discussion.
In addition to Twitter, other services are now using hashtags. On Google+, they play a role in real-time search, and on Instagram and Pinterest they are also used to tag