Citizens buy first day covers at the release ceremony of "Internet Life", a special stamp set issued by China Post to mark the 20th anniversary of China's internet era, in Nanjing, capital of East China's Jiangsu province, April 20, 2014. China officially gained internet access on April 20, 1994. Within two decades, internet has played a vital part of the country's everyday life. The special stamp set contains four commemorative stamps with their respective themes -- "online communication", "e-commerce", "mobile connection" and "cloud computing". [Photo/Xinhua]

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