5. AOL
> Pct. of all time spent online: 2.5%
> Desktop visitors: 117.6 million
> Mobile visitors: 62.4 million

AOL Inc. (NYSE: AOL) has transformed itself from a company that was primarily providing dial-up Internet service into a media company. The company’s most popular news website is The Huffington Post, which it bought in 2011. The Huffington Post, like many news outlets, recently has devoted many of its resources to video programming. The company launched its news streaming service, HuffPost Live, in August 2012. The service was created with the intent to engage users. Features such as the “join this segment” let viewers speak their mind via webcam.

4. Microsoft
> Pct. of all time spent online: 4.9%
> Desktop visitors: 170.9 million
> Mobile visitors: 55.2 million

Microsoft Corp.’s (NASDAQ: MSFT) sites, including MSN, Hotmail and Bing, had nearly 169 million unique visitors in December, more than any other Web property except for Google and Yahoo! Bing, the second-most popular search engine behind Google, has seen its share of search grow slightly, from 15.1% of all searches in December 2011 to 16.3% in 2012. Microsoft has made a major push into mobile with its new Windows Surface Tablet, which was released late in 2012.

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3. Yahoo!
> Pct. of all time spent online: 7.0%
> Desktop visitors: 185.8 million
> Mobile visitors: 92.2 million

Although Yahoo! Inc. (NASDAQ: YHOO) has struggled in recent years because it has lost advertising market share to Facebook and Google, it is still the most popular portal on the Web. The company recently redesigned its website in order to make it more personalized. The site includes a live news feed of articles that are customized to the visitors’ interests and to what their friends share on social networks. The company has made significant strides in mobile as well. More than 92 million people accessed at least one of the site’s properties through a mobile device in December 2012.

2. Google
> Pct. of all time spent online: 10.0%
> Desktop visitors: 193.8 million
> Mobile visitors: 113.7 million

In December alone, Google Inc. (NASDAQ: GOOG) sites had almost 194 million desktop unique visitors and nearly 114 million mobile visitors throughout the country. Google owns YouTube, by far the most visited video site. In 2012, more than 188 billion videos were streamed on the website, according to comScore. In comparison, only about 8.9 billion videos were streamed on Hulu, the second-most visited video property. Despite becoming a multidimensional company over the years, Google shows no signs of letting up on its original business of search. A whopping 66.7% of all Internet searches were conducted through Google in December 2012, up from 65.9% during the same month of 2011.

1. Facebook.com
> Pct. of all time spent online: 10.8%
> Desktop visitors: 150.3 million
> Mobile visitors: 97.7 million

Responsible for 10.8% of all time on the Internet, more time is spent on Facebook than any other site. Of all the time spent on the different social networking sites, 83% is spent on Facebook. Facebook Inc. (NASDAQ: FB) also has made very significant inroads in mobile, with time on Facebook’s smartphone applications making up 23% of all time on apps. However, Americans have shown they are willing to give up Facebook — albeit only for a short time. According to a study by the Pew Internet and American Life Project, 61% of the site’s active users have taken a multiweek break from the social network at some point. Furthermore, 27% of people surveyed said they planned to spend less time on Facebook in 2013, while only 3% intended to spend more time on the site.

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