Hashtag is a word creation from hash, the hash sign (#), and a tag. In a hashtag, the tag is introduced by a hash (#), executed by a sequence of letters, and ended by a space
. Hashtags are used
intweets from Twitter and are placed before the tag content. They highlight a word or string of characters. The hash itself is followed by a letter-digit creation that must not be interrupted by a space, punctuation, or special character
. Example: #greatconcert.