are you familiar of HashTag?
According to Wikipedia,
A hashtag is a word or an unspaced phrase prefixed with the number sign ("
#"). It is a form of metadata tag. Words or phrases in messages on microblogging and social networking services such as Facebook, Google+, Instagram, Twitter, or VK may be tagged by entering "#" before them,[1] either as they appear in a sentence (e.g., "New artists announced for #SXSW2014 Music Festival")[2] or appended to it. The term "hashtag" can also refer to the hash symbol itself when used within the context of reciting a hashtag.[3]Hashtags make it possible to group such messages, and a search for the hashtag returns the set of messages that contain it. A hashtag is only connected to a specific medium and can therefore not be linked and connected to pictures or messages from different platforms.[citation needed]
Because of its widespread use, the word "hashtag" was added to the Oxford English Dictionary in June 2014.[4][5]

