At 12:50 pm on March 21st, 2006, Twitter co-founder Jack Dorsey sent out the first ever tweet. It said “just setting up my twttr.” Now, six years later, Twitter is an indelible part of millions of people’s lives.

That’s right, today is Twitters 6th birthday. It’s reading Berenstain Bears books, starting to get a little more coordinated with sports, and it’s language skills are improving.

Well, we’re not too sure about that last one. One thing we are sure about is that Twitter is still growing (now officially faster than Facebook). And Twitter is reporting that they now have 140 million active users. Here’s what they had to say in a blog post:

Six years may not be very long in human terms, but it’s been quite an enormous span for the thing we know and love as Twitter. When @jack first sketched out his notion in March 2006, no one could have predicted the trajectory of this new communication tool. Now it seems that there are as many ways to express yourself in 140 characters as there are people doing it. And at last check, there are more than 140 million active users (there’s that number again) — and today we see 340 million Tweets a day. That’s more than 1 billion every 3 days. However concisely, it turns out there’s plenty to say.

Last September, Twitter CEO Dick Costolo said that there were 100 million active Twitter users. He defined “active” as users who log on at least once a month. At that time, he said half of the active users log on every day.

So, by this stretch, let’s just say that Twitter’s self-announced 140 million active users roughly translates into 70 million users that log on every single day. That’s a pretty big community. When you talk about just registered users, it gets even bigger. Twitter just hit 500 million of those last month.

Here’s to another happy six years, Twitter!