If you've spent any time online, you will have seen a hashtag. In fact, you might have seen them in commercials on TV, on billboards, or spoken out loud too. Which may have prompted you to ask, what is a hashtag?

If so, you've come to the right place. We're going to explain what a hashtag is, where hashtags originated, and how to use hashtags correctly. When you reach the end of this article you'll be a hashtag master!

What Is a Hashtag?

A hashtag is used primarily on social network sites like Twitter, Instagram, Facebook, Pinterest, and LinkedIn. Most of the top social media sites use them in one way or another.

Collins Dictionary defines a hashtag as:

A word or phrase that has the hash symbol (#) in front of it, to show that it is the topic of a message on social media.

Using a hashtag is a way to mark your message as belonging to a topic or theme. Other people can then search for this hashtag to find messages about something that interests them. A hashtag is often hyperlinked, so you can click it and be taken directly to those search results.

A hashtag is formatted by a # sign followed by text. The # symbol itself is sometimes called a hashtag, but the two aren't the same. The # symbol is actually called a number sign, pound sign, octothorpe, or hash. Its usage varies by country, but it is often used alongside ordinal numbers or as a symbol for the pound as a unit of weight.

As such, the term hashtag primarily has purpose online on social networks. Here's an example of a hashtag being used on Twitter:

Who Invented the Hashtag?

The idea of using a hashtag as we know it was first proposed by Chris Messina:

If you're interested on his detailed thoughts, check out his Factory Joe blog post from 2007.

At that point, he floated the phrase "tag channels" rather than the now-ubiquitous "hashtag". That's because the # sign already had a specific meaning online. Internet Relay Chat (IRC), a form of text-based live messaging, is split into different chat rooms (or "channels") that are preceded by the # sign. For example, you could have different channels like #animals and #food.

It should be noted that IRC still exists, and here's how to create your own IRC channel.

The name hashtag came from Stowe Boyd, in his blog post response to Chris. However, despite all of this happening in 2007, hashtags didn't immediately take off.

It wasn't until events like the 2007 San Diego forest fires and the 2009-2010 Iranian election protests that hashtags started to gain traction. In 2009, Twitter began linking hyperlinks to the search results, and in 2010 Twitter started to display popular hashtags on its homepage.

From there the hashtag only grew, expanding from Twitter and spreading to many other websites and services.

How to Use a Hashtag

Hashtag on a screen
Image Credit: John Cameron/Unsplash

Anyone has the power to create a new hashtag. And they're used by individuals and businesses alike. Simply type the # sign, followed by a word or phrase, and your hashtag is done. If someone else has used the same hashtag previously, your post will appear alongside those when people search for that hashtag.

There are some rules you should follow to ensure your hashtag displays and functions correctly:

  • A hashtag should always begin with the # symbol. If it's not the first thing in your message, ensure there's a space beforehand. For example, "I love tech #makeuseof" is good, while "I love tech#makeuseof" is not.
  • Don't use punctuation, special characters or spaces in a hashtag because it won't work. For example, "I love tech #make use of" would only hashtag the word "make".
  • You can use capital letters in a hashtag, but this is only for readability. For example, both #makeuseof and #MakeUseOf are the same hashtag.

Each service will also have its own rules on using hashtags. For example, Instagram only allows up to 30 hashtags on a post. There are also unwritten social network rules, such as do keep the hashtags specific, don't overload your post with them, don't use irrelevant ones, and don't be vulgar.

When to Use a Hashtag

You can use a hashtag whenever you want. There's nothing to stop you---type a # sign followed by some text and you've created a hashtag.

Using Hashtags for Events

Generally, the best use of a hashtag is when you want to create or join a discussion around a specific topic. Let's say your local town of Springfield is having a fun run. You could put a message on social media like:

Best of luck to my friend Homer today! As long as you get across the finish line, that's all that matters. #SpringfieldFunRun

Other people could then use the same #SpringfieldFunRun hashtag. Then, when others click that hashtag or search for it, they will see all the messages related to that event.

Using Hashtags for Businesses

Equally, hashtags can be used on a global level by businesses. Here's an example from the Star Wars Twitter account, which used multiple hashtags to promote The Mandalorian on Disney Plus:

You might also notice hashtags appear offline in all sorts of places, like movie trailers, billboards, and TV commercials. That's because these businesses want you to go online, discuss their product or service, and use the hashtag to create a buzz.

Using Hashtags for Comedy

Hashtags can also be used ironically or sarcastically. This is often when the user isn't interested in grouping their message to a discussion, but instead trying to be funny. For example:

Just ate a huge cake all to myself. I feel great! #DietStartsNow

This comedic application of the hashtag also applies when it's spoken out loud because, obviously, the group and search functionality of a hashtag isn't possible to achieve in speech.

Using Hashtags for Causes

Some hashtags have transcended their online origin. This can be seen in the phrase "Je suis Charlie", meaning "I am Charlie", which was a slogan created to show solidarity after the shootings at the Charlie Hebdo magazine in 2015.

The statement began as #jesuischarlie on Twitter before being used in music, cartoons, and newspapers. The hashtag then morphed into the more general #jesuis, which was used globally as a sign of alignment to different causes.

Use Hashtags to Get Noticed on Social Media

Now you know what a hashtag is, how the term originated, and how to use hashtags. So get out there and start using hashtags to your heart's content!

Hashtags are also a good way to get noticed on social media. For more tips, our guide will help you get noticed on Instagram.