If you are on Twitter, you may notice some socially savvy tweeters mistakingly, or at least it seems like it, putting a dot in front of @username mentioned tweets. Odds are you've never heard of the infamous Twitter dot, but it's a secret that could be preventing you from reaching out to your potential customer base on social media.
Twitter does not want to clutter up other people's timelines with personal conversations, so they limit tweets that start with @username mentions to you, the person mentioned, and any of your followers that also follow that specific person. The problem with that is, is mentions aren't always meant to be personal. Sometimes you are mentioning a company or famous person and want to share your message to all of your followers. Other times, as seen in this real-life example, you could be live tweeting an event and your followers are missing out on the news.
The fix to this is the aforementioned Twitter dot, or a period on your keyboard. Putting the dot at the start of your tweet eliminates the tweet starting with an @username and allows your message to be seen by everyone following you. Allowing you to share your message to your entire audience, not just a few people.
Remember that the use of the dot only applies to tweets that start with someone's handle, or the @username mentioned above. If the handle is in the middle, or end of the tweet, the message will go out to all of your followers.