Twitter bringing real-time notifications on the web. When someone engages with your Twitter account you will be notify if you’re using Twitter.com on your system.
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Image Credit – Wired.com

Twitter officially announced on their blog post says “When it comes to your interactions on Twitter, it should be easy for you to stay connected to what’s relevant. With this in mind, we’re bringing you real-time notifications on twitter.com when someone is engaging with your Tweets.”
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You will receive notifications if someone has replied to your tweet, someone sent you a message, favorited or retweeted your tweets, some one follows you etc.

The notification systems are interactive and you can reply, favorite, retweet, and follow right from the notifications. Twitter will rolling this feature in the coming weeks. If you are eligible to get this feature Twitter will give you an option on your settings page for choosing which notifications you want to see.