Hashtags are essentially tags that indicate the content of the post created. You can add a hashtag to your post at anytime by placing the pound sign (#) in front of the word you wish to tag.
Example: The #president spoke today at the #white #house.
In the post above, 3 of the words are tagged. This means that people can find this post by searching for the words "president", "white", and "house". Also, this makes the words act like links that search for these terms. This means someone can click on this hashtag inside of your post, and see all other posts and content that contain that same hashtag.
Hashtags are also shown in the "Current Trends" area of the website, which indicates which topics/hashtags are being most talked about within the past 24 hours. You can click on any of the hashtags in this area and see all posts that contain those hashtags.
Hashtags improve post visibility in this way, so knowing how to tag your posts is important. Also, it can serve as a negative as well. if you keep tagging your posts with irrelevant topic tags, people will not take your posts seriously. So use them sparingly but effectively.
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