The internet has played a key role in aiding China's battle against COVID-19 in 2020, with the total number of registered "health QR code" users nearing 900 million since the outbreak, says a report on China's internet development unveiled Wednesday. Health QR codes, automatically generated quick response codes assigned to people as an indicator of their health status, were introduced by a national integrated government service platform among China's wider epidemic prevention and control efforts. Code-based access has been realized in most parts of the country, with big data playing its role in COVID-19 control and the resumption of business and manufacturing, according to the statistical report released by the China Internet Network Information Center.