ASP.NET Core is a free and open-source web framework developed by Microsoft as the next generation of ASP.NET. It is a modular framework that can run on both the full .NET Framework on Windows and cross-platform .NET Core. Some key features include hosting on IIS or standalone, cloud-optimized runtime, and support for JIT and AOT compilers. Major releases include .NET Core 1.0 in June 2016 and .NET Core 2.0 planned for Q3 2017. Benchmark tests show ASP.NET Core can serve over 2300% more requests per second than previous versions.