Social Media Day is being celebrated around the world today on Twitter, Facebook and at meetups around the world.

Many of us use social networks (66 percent of adults as of March, according to the Social Skinny) to stay in touch with old friends, rant about the state of politics or update our status to let the world know we just ate a Peanut Butter M&M. But the impact of social media on our daily lives may be greater than you think. It's been credited, in the case of Facebook, with being the catalyst for the Arab Spring. Twitter's traffic grew exponentially when a massive 2011 earthquake and tsunami struck Japan near its Oshika Peninsula, damaging the Fukashima Daiichi Nuclear Power Plant and causing radiation fears to sweep the region and country. And even First Lady Michelle Obama is an active user on Pinterest.

Of the people who use social networks, half log on first thing in the morning to their preferred site, whether it be Facebook, Twitter, Pinterest, Reddit, Instagram, LinkedIn or another social media website, according to The Social Skinny.

Can the impact of social media be measured? Now, it can, quantitatively, according to Gary Hayes, an executive producer at the Australian Broadcasting Company, who created Gary's Social Media Count -- a flash-based app that tracks how many Facebook likes, comments, tweets, and Google + buttons are pressed, among other social media actions. (You can see this app here.)

Here are some interesting tidbits from Gary's Social Media Count:

  • There are 3.2 billion likes and comments made on Facebook each day
  • 175 million tweets are sent on Twitter a day
  • The Google+ button is pressed 5 billion times a day
  • 17 million visitors go on Pinterest a day
  • Nearly 830,000 YouTube videos are uploaded daily
  • Every day, 526 million people sign up for Facebook
  • Google+ increases its number of users by 625,000 a day
  • Every second, 58 photos are uploaded through Instagram
  • StumbleUpon adds 2.2 million pages a day
  • 300 million photos are uploaded to Facebook each day

Hayes' figures are not the only data on social media. The Social Skinny has a rundown of various social networks and their number of registered users as of February. Here's how it breaks down:

Facebook: 850 million users (as of February)

Twitter: 500 million registered users, 200 million active

LinkedIn: 135 million users

Google+: 90 million users

Pinterest: 10.4 million users

The tech website Mashable, which spearheaded Social Media Day in 2010, created the event as a way to recognize the digital revolution happening right before our eyes.

To participate in Social Media Day, click here, where you can find Mashable Meetups in your city.