What is a hashtag?
It's nothing but a hash followed by a tag. The tag is a label, or key word(s) that indicate(s) a topic of discussion. So, hashtag comprises a word, or a group of words without space in between them, and prefixed with the hash symbol, #. (Wikipedia entry on hashtag)
For eg: #bbcworldcup, #BringBackOurGirls, #Firstboss
The hashtag was first used on Twitter, and works best there. It serves to group together messages on a particular topic. It makes it easy for people to search messages on that topic by entering the hashtag in the search box on Twitter.
But why have a hashtag when we can search for tweets by simply typing out a word or a phrase like we search for websites in Google?
That's right. If you want to search for all tweets on Obama, you can key in Obama in the search box and get all the tweets with the word Obama in them. So is the case with any other word or phrase. For example: healthcare, MH370, Iraq fighting etc. Indeed, you can search for tweets on Twitter exactly like you search for websites on Google.
Why use hashtag?
A news organization like the BBC or the New York Times, or institutions or advocacy groups, or individual Twitter users, may create a hashtag for an issue or an event. They publicize this hashtag, calling on people to use that hashtag with their tweets. The aim is to bunch all the tweets on that issue or event under one hashtag. It also helps people looking for tweets on a particular issue or event or a person.
For example: for the world cup football matches currently on in Brazil, BBC has created a hashtag #bbcworldcup, So all tweets on BBC related to the world cup has this hashtag. By tweeting with this hashtag, you also stand a chance of getting your tweets featured in the live stream on the BBC site.
The most famous hashtag in recent times was "#BringBackOurGirls". It was created after the abduction of over 200 schoolchildren by militants in Nigeria on April 14. (More from BBC)
There was intense debate online about who created the #BringBackOurGirls hashtag. The BBC, after a thorough check, says it was first used on April 23 by Ibrahim M Abdullahi, a lawyer in Nigeria. (More)
The BBC has some interesting statistics about the #BringBackOurGirls
The purpose of creating that hashtag was to group all tweets on this important incident under one label. Whether the online activism achieved anything tangible is still being debated.
Anyone can create a hashtag. For example, you can tweet about your first boss, with the hashtag #FirstBoss. Popularize it, and get people to tweet with this hashtag. So, if you search Twitter for this hashtag, you will get to see all tweets on this topic.
Wrong use of hashtag
Merely putting a hash sign in front of a word does not make that word a hashtag. It serves any purpose only if it's clickable. So, no point using it in WhatsApp messages and SMSes. Though it's most commonly used in Twitter, Facebook too lets you see a feed of all posts with a particular hashtag.
- Hashtags should be as short as possible. Because, longer the hashtag, fewer will be characters in your tweet.
- If a hashtag has more than one word, then there shouldn't be any space between the words.
- It should be unique, or else it defeats the purpose of creating one.
- Hashtag works only on the website it has been used. You can search on Twitter hashtags that are used on Facebook.