TurnKey ASP .NET Core helps save you time and money by providing a ready-to-run ASP .NET Core solution that is secure, supported and easy to maintain. The system auto-updates itself with security fixes and is built in a transparent 100% open source process free of hidden backdoors. .NET Core is the successor to the .NET Framework, it's free and open source provided by Microsoft. ASP.NET Core is the .NET Core version of ASP.NET: a web application framework for developing dynamic web pages with C#.