New York: With 320 million users including celebrities such as Harry Styles, Katy Perry and Justin Bieber on its platform, the micro-blogging site Twitter on Monday wrote a 140-character thank you note to its users as it celebrated its 10th anniversary.

Twitter users are creating 500 million tweets per day and 200 billion tweets every year.

‘On March 21, ten years ago, it began with a single Tweet. Since then, every moment of every day, people connect about the things they care about most - all over the world,’ Twitter posted.

‘As we mark this milestone, it's you we want to celebrate. As 21 March begins around the world, each of our global offices will kick off the day by showing our appreciation and gratitude - starting in Sydney and following the sun to headquarters in San Francisco. We are excited to celebrate with all of you,’ the post further read.

Twitter CEO Jack Dorsey said last week that while several changes are being planned at the company, its 140-character limit represents a beautiful constraint, which helps deliver strong statements.

The short character limit for tweets is an element that gives Twitter a unique identity.

Appearing on a TV show, Dorsey said that the 140-character limit is ‘a beautiful constraint’ and that Twitter ‘will never lose that feeling’.

‘It's (140-characters) staying. It's a good constraint for us, and it allows for of-the-moment brevity… We're changing a lot. We're always going to make Twitter better,’ he was quoted as saying.

The 140-character limit has been around as long as Twitter has and has become part of the product's personality. Twitter is also working on the idea of changing its reverse chronological timeline.

‘Throughout the years, you've made Twitter what it is today and you're shaping what it will be in the future. Thank you for making history, driving change, lifting each other up and laughing together every day,’ Twitter post stated.

Twitter has also proved itself as an excellent platform to raise awareness about political topics, spread political messages and coordinate collective action.

The use of Twitter by US Republican presidential candidate Donald Trump ‘as a microphone’ is one of the several such cases to prove the point.

In 2009, flight number 1549 of the US Airways made an emergency landing in the Hudson River between New York City and Weehawken in New Jersey.

The first image of the rescue mission in which all the 155 passengers were evacuated to safety were taken by a Twitter user and it became viral within minutes of uploading it on the platform.