Five years ago this week, a small team of people started working on a prototype of the service that we now know as Twitter. On March 21, 2006, Jack Dorsey (@jack) sent the first Tweet. Today, on every measure of growth and engagement, Twitter is growing at a record pace. Here are some numbers: #tweets 3 years, 2 months and 1 day. The time it took from the first Tweet to the billionth Tweet. 1 week
![#numbers](https://cdn-ak-scissors.b.st-hatena.com/image/square/4f3072d7d302c3605bc8f83324ce8ec3ef49708f/height=288;version=1;width=512/https%3A%2F%2Fcdn.cms-twdigitalassets.com%2Fcontent%2Fdam%2Fblog-twitter%2Fx%2Fblog_x_card.png.twimg.768.png)