Originally, Twitter had no character limit.  Messages that exceeded 160 characters (the typical SMS text limit) were split into multiple texts and delivered sequentially.

The message bill got high for Twitter and there were bugs with delivery.

Twitter solved the mounting problems by putting a 140 character cap on messages. This left 20 characters for a Twitter handle and the colon before the text.

Facebook generates more than $2 billion in annual revenue through ads, games, gifts, and cash cards.

Facebook makes most of its money through ads, which can be geotargeted or contextually targeted. Facebook also has a good deal of psychographic information it can share with advertisers based on users' profiles. Ads are shown on the right side of every page.

It also makes money via games which are primarily provided by Zynga.  Facebook games include Mafia Wars and Farmville. 

"Zynga is able to exchange in-game money and items for real money to a fraction of those users. Whenever Zynga does so, Facebook takes a percentage of the profits for themselves. Additionally, by hosting its games on Facebook, Zynga receives a large number of visitors to their own website, which Facebook charges them for," writes Tech FAQ.

Users can also buy and send Facebook Gifts to friends. Most are free, but some of them must be purchased.  Facebook also has cash cards that can be bought in stores like Walmart and used on its site.

Cloud computing means storing things online rather than on your computer.

The "cloud" is a network of computers that local computers can access. Before cloud computing, if you wanted to run software on your computer, you had to install it.  Cloud computing promises you'll never have to install anything again.

Instead, you'll run an interface software that's as simple to use as a web browser, and you'll be instantly connected to everything you need from any device -- from your music, to apps, to passwords, address books and banking information. 

Every place you connect to the Internet will be like your personal computer.

From the iPod to the iPad, Apple products have begun with an "i" since the iMac was released in 1998.

Steve Jobs explained the use of the letter then. It stands for a few things: Internet, Individual, Instruct, Inform, and Inspire.

"iMac comes from the marriage of the excitement of the Internet with the simplicity of Macintosh," said Jobs.

"'i' also means some other things to us.  We are a personal computer company and, although this product is born to network, it also is a beautiful stand-alone product. It's perfect for finding a tremendous amount of information over the Internet, and we hope as you see the product it will inspire us all to make even better products in the future."

Here's the 1998 clip below:

Google makes money primarily from advertising.

Google Adwords is an auction-based program that allows advertisers to contextually target search terms. It also allows advertisers to contextually target web pages within Google's network. 

Many web publishers use Google's ad network on their pages (via Google AdSense) and get paid for serving the placements on their sites.

Google ads appear in multiple forms. There are sponsored search results for both terms and images, Gmail ads, YouTube ads and more.  Google also makes money by licensing Google Apps that come on Android phones, such as Gmail, Search and Maps.

In 2010, Google generated $29.3 billion in revenue.

Bluetooth technology originated in Scandinavia. It was intended to unite multinational companies, so the inventors wanted to name it after a king who united countries. 

Bluetooth was named after a Danish king, Harald "Blåtand" Gormsson.  Blatand loosely translates to "Blue Tooth." 

Some say Gormsson was given the nickname because he enjoyed blueberries, and his teeth were frequently discolored.

The New Yorker wrote a profile on Mark Zuckerberg.

In the interview, Zuckerberg revealed why Facebook is blue: he's red-green colorblind.

"Blue is the richest color for me. I can see all of blue," he says.

They don't. The forward slashes are there solely for aesthetic purposes.

Google was named after a math term, googol.

One googol is 1.0 × 10^100.

The birds are so angry because a group of green pigs stole their eggs.

When Angry Birds was being developed, the Rovio crew needed an opponent for their legless, wingless birds.

At that time, Swine Flu was a hot news topic, so they made pigs the enemies.

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