what the heck is a hashtag?

Hashtag
A really fucking annoying hipster version of the pound sign (#)
Originated from twitter but is everywhere. Hipsters say it out loud.
Hipster: "just got new tampons! 'Hashtag' awesome!
Everyone else: shut the fuck up its called a 'pound'
#hipster#hashtag#twitter#pound#annoying

(on social media sites such as Twitter) a word or phrase preceded by a hash or pound sign (#) and used to identify messages on a specific topic.
"spammers often broadcast tweets with popular hashtags even if the tweet has nothing to do with them"

A hashtag is a thing used on Twitter to categorize posts. What you do is, you type the number/pound sign, this thing #, and then a topic of your post. So if I posted a picture of a dog, I could hashtag the post with #dogs. That way, if you wanted to find posts related to dogs, you could search on Twitter for #dogs and find all dog-related posts. Likewise, you can hashtag things for any other subject, #politics, #currentevents, #basketball, and so on.

Alternatively, people add hashtags into comments outside of Twitter for satirical or sarcastic purposes.

#

It's an octothorpe

#hi

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