Sogou, Inc. is an innovator in search and a leader in China's Internet industry. With a mission to make it easy to communicate and get information, Sogou has grown to become the fourth largest Internet company in China based on monthly active users (MAUs). Sogou's differentiated search services, the industry leading Sogou Input Method, the robust ecosystem it has built and shared with Tencent and other strategic partners, as well as significant breakthroughs in AI, uniquely positions Sogou to capture the opportunities in China's search and Internet industry.
Sogou Search is China's second largest search engine by mobile queries. Sogou is committed to building an efficient and knowledgeable search platform that provides high-quality content. It focuses on delivering authoritative search results to users with highly relevant results that accurately respond to user queries. Sogou has also enhanced healthcare search services and established a healthcare content ecosystem that has become an industry benchmark. With the ongoing integration of AI technology, Sogou Search continues to evolve into an intelligent question and answering ("Q&A") engine.
Through a robust ecosystem Sogou has built and shared with Tencent and other strategic partners, it also delivers differentiated content to users, including search access to the vast content from Tencent's Weixin/WeChat Official Accounts. Sogou Search is the default search engine for a range of Tencent products that offer general search functions. Sogou Search also continues to be the preferred search engine on Weixin/WeChat for third-party search services to access external Internet content. Weixin/WeChat and Sogou intend to extend this partnership year to year until 2023 as part of the overall framework agreement that Sogou and Tencent entered in September 2018.
Sogou Input Method is the largest Chinese language input software by MAU for both mobile and PC. It is also the largest voice app in China and the first cloud-based Chinese language input software. It interfaces with virtually all applications that involve Chinese-language input, generating massive, high-quality data that is critical to our big data capabilities. Sogou Input Method anticipates users' search intentions in real time and allows them to search directly with Sogou Search through its embedded search function, generating a significant portion of our organic search traffic. It also provides targeted recommendations to address users' variety of browsing and search needs emerging in chats. Thanks to a number of industry-leading product innovations, Sogou Input Method continues to evolve from a utility software to an AI-enabled communication assistant.
Sogou Input Method is an important driver for our Recommendation Service that we have been building to further unlock the commercial value of our large user base and advanced big data capabilities.