Google data centers in late 2013 and began selling off the barges in 2014. Most of the software stack that Google uses on their servers was developed in-house. According to a well-known Google employee, C++, Java, Python and (more recently) Go are favored over other programming languages. For example, the back end of Gmail is written in Java and the back end of Google Search is written in C++. Google has acknowledged that Python has played an important role from the beginning, and that it continues to do so as the system grows and evolves. The software that runs the Google infrastructure includes:
World IPv6 Day and World IPv6 Launch Day IPv6 Day. included some of the most heavily accessed destinations on the Internet, content distribution networks, as well as various Internet service and infrastructure providers including: Comcast, Google, Yahoo, Facebook, Yandex YouTube, Akamai Technologies, Limelight Networks, Microsoft, Vonage, AOL, Mapquest, T-Online, Cisco, Juniper Networks, Huawei, the US Department of Commerce, MasterCard, the BBC, and Telmex. Major carriers measured the percentage of IPv6 traffic of all Internet traffic as increasing from 0.024 to 0.041 with respect to native and tunneled stacks combined. Most IPv6 traffic in consumer access networks was to Google sites. Demonstrating the need for content sites to adopt