More than half a billion Chinese are now online

Tang Ming Tung | Flickr | Getty Images

China's booming netizen population has reached 591 million, an increase of 10 percent from a year ago, according to official data, led by growth in users accessing the internet through their mobile phones.

The overall internet penetration rate climbed to 44.1 percent at the end of June, from 42.1 percent at the end of 2012, a mid-year report by China Internet Network Information Center (CNNIC), a non-profit group with official ties to the government, showed.

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This compares to 78.6 percent in North America and 63.2 percent in Europe, according to Internet World Statistic, a website that tracks data relating to internet usage.

An increasing number of users are accessing the internet through their mobile devices as compared to their PCs, according to CNNIC. The number of mobile internet users grew to 464 million from 420 million in December 2012.

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Users accessing the internet via mobile devices first exceeded PCs in June 2012 and the trend has since continued, driven by the affordability of smartphones in the mainland and the attractiveness of mobile applications that require internet access.

"As the low-end smartphone penetration rate continued to rise this year, we expect mobile internet usage to continue to outpace the growth rate of traditional PC internet users," Alicia Yap, an analyst at Barclays, wrote.

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Alongside the growth in internet penetration, China has also seen an expansion of its microblogging population. The total number of internet users in microblogs reached 331 million, compared with 309 million at the end of 2012.

In the absence of social media websites like Facebook and Twitter, local microblogging websites have surged in popularity in recent years, becoming a primary platform for citizens to engage in discussion on political and social issues, communicate with government officials and obtain local news.

By CNBC's Ansuya Harjani