A hashtag is to Twitter what a tag is to the internet in general. It’s a key word that defines the topic you are writing about on Twitter thus making it easier to search for information on that topic. A Twitter hashtag is created by placing the hash or pound (#) sign in front of the key word. So, if you are writing about Obama, you make Obama your hashtag by placing a # in front of it, so anyone interested in the subject who searches this hashtag can access your Tweet (message).
[myNetWords.com]



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