
Hashtags are a way of organizing conversations in popular social websites like Twitter and Instagram.
You can learn about the history of the hashtag on my favorite podcast, 99% Invisible. Apparently, they were originally called "Octothorpes". It's really interesting!
Hashtags work like this:
Say you're on Twitter and you're witnessing Manhattanhenge for the first time. So, like any enthusiastic social media user, you immediately post it to Twitter and say
Sunset directly in line with skyscrapers in Manhattan! This only happens twice a year! #manhattenhenge
That little pound symbol or "hashtag", as it's referred to when you're using in social media, automatically takes your tweet and places it an area on Twitter where all the other people witnessing Manhattanhenge are tweeting and including the same exact hashtag. All of those posts get organized into an area called a "feed". On Twitter, it looks like this:

The purpose of hashtags are to organize conversations to facilitate the discovery of new things, people, and brands. For example, if you've never heard of Manhattanhenge, you could go on twitter right now and search for that hashtag and it will pull up all the people that are talking about Manhattanhenge. It's a pretty powerful concept.
Your small business can use hashtags to attract new customers by including relevant hashtags in your tweets or Instagram posts. For example, if you sell jewelry, you could include hashtags such as these: #handmade #madeinnyc #earrings #jewelry
Adding hashtags to your posts is a great way to organically increase followers and get more likes on your posts.
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