Ever wondered how much email is sent each year? How many websites there are online? How many videos there are on YouTube? How much people twitter? Etc? Pingdom composed a nice blog about it here, so either click the link for the full post or read some quick stats below:

Email

• 90 trillion – The number of emails sent on the Internet in 2009.
• 247 billion – Average number of email messages per day.
• 1.4 billion – The number of email users worldwide.
• 100 million – New email users since the year before.
• 81% – The percentage of emails that were spam.
• 92% – Peak spam levels late in the year.
• 24% – Increase in spam since last year.
• 200 billion – The number of spam emails per day (assuming 81% are spam).

Websites

• 234 million – The number of websites as of December 2009.
• 47 million – Added websites in 2009.

Web servers

• 13.9% – The growth of Apache websites in 2009.
• -22.1% – The growth of IIS websites in 2009.
• 35.0% – The growth of Google GFE websites in 2009.
• 384.4% – The growth of Nginx websites in 2009.
• -72.4% – The growth of Lighttpd websites in 2009.

Domain names

• 81.8 million – .COM domain names at the end of 2009.
• 12.3 million – .NET domain names at the end of 2009.
• 7.8 million – .ORG domain names at the end of 2009.
• 76.3 million – The number of country code top-level domains (e.g. .CN, .UK, .DE, etc.).
• 187 million – The number of domain names across all top-level domains (October 2009).
• 8% – The increase in domain names since the year before.

Internet users

• 1.73 billion – Internet users worldwide (September 2009).
• 18% – Increase in Internet users since the previous year.
• 738,257,230 – Internet users in Asia.
• 418,029,796 – Internet users in Europe.
• 252,908,000 – Internet users in North America.
• 179,031,479 – Internet users in Latin America / Caribbean.
• 67,371,700 – Internet users in Africa.
• 57,425,046 – Internet users in the Middle East.
• 20,970,490 – Internet users in Oceania / Australia.

Social media

• 126 million – The number of blogs on the Internet (as tracked by BlogPulse).
• 84% – Percent of social network sites with more women than men.
• 27.3 million – Number of tweets on Twitter per day (November, 2009)
• 57% – Percentage of Twitter’s user base located in the United States.
• 4.25 million – People following @aplusk (Ashton Kutcher, Twitter’s most followed user).
• 350 million – People on Facebook.
• 50% – Percentage of Facebook users that log in every day.
• 500,000 – The number of active Facebook applications.

Images

• 4 billion – Photos hosted by Flickr (October 2009).
• 2.5 billion – Photos uploaded each month to Facebook.
• 30 billion – At the current rate, the number of photos uploaded to Facebook per year.

Videos

• 1 billion – The total number of videos YouTube serves in one day.
• 12.2 billion – Videos viewed per month on YouTube in the US (November 2009).
• 924 million – Videos viewed per month on Hulu in the US (November 2009).
• 182 – The number of online videos the average Internet user watches in a month (USA).
• 82% – Percentage of Internet users that view videos online (USA).
• 39.4% – YouTube online video market share (USA).
• 81.9% – Percentage of embedded videos on blogs that are YouTube videos.

Web browsers

Malicious software

• 148,000 – New zombie computers created per day (used in botnets for sending spam, etc.)
• 2.6 million – Amount of malicious code threats at the start of 2009 (viruses, trojans, etc.)
• 921,143 – The number of new malicious code signatures added by Symantec in Q4 2009.

Main data source is Pingdom.com, you'll find the full list of data sources in their blog post.