NEW DELHI: India will overtake the US as the second-largest Internet user base in the world by next month, behind only China, which has more than 600 million subscribers.The number of Internet users in India is expected to reach 402 million by December, a growth of 49 per cent over last year, according to a report by the Internet and Mobile Association of India and IMRB International While it took more than a decade to go from 10 million Internet users to 100 million and three years from 100 million to 200 million, it's taken only a year to go from 300 million to 400 million users."The growth in the number of Internet users is great news for the industry because the mass base is growing," said Nilotpal Chakravarti, associate vice-president at IAMAI He said with more people getting online and becoming aware of the benefits of the Internet and ecommerce, there is great potential for growth. "The number of users in India is expected to touch 500 million by next year. This is especially good news for the ecommerce digital industries because now they will have a mass base of consumers," he said. Internet users in the top eight metros accounted for 31 per cent of the total of 375 million in October. Mumbai had the largest base of monthly active users among top metros. Smaller cities saw a 60 per cent jump in total number and Surat emerged with the highest Internet ownership in this category.While the urban user base expanded almost 40 per cent until October, growth in rural India was 77 per cent. Mobile phones were the main driver of growth in rural areas, where active mobile Internet users are expected to reach 87 million by December and 109 million by June, according to the report."To tap such a huge rural base of potential mobile Internet users, digital has to be the core of any company's strategy. The data usage is poised to increase to an unprecedented level and the digitally enabled sectors are up for steep growth in the coming five years," said the report.In urban areas, online communication continued to be the primary purpose for accessing the Internet, followed by social networking and entertainment. In rural areas, entertainment and social networking led the usage categories. Gaming through social networking sites picked up in rural areas, with 36 per cent of the user base, up from 21 per cent last year.