ASP.NET is a server-side framework that enables programmers to build dynamic websites, services, and applications. ASP.NET pages are officially referred to as Web Forms.
ASP.NET MVC is an alternative way to build web applications with ASP.NET. It doesn’t replace ASP.NET Web Forms, it simply uses a different architectural pattern.
MVC stands for Model-View-Controller. This architectural pattern separates an application into three pieces. These components are the model, view, and controller.
.NET Core is a high speed and lightweight platform used to develop web services and applications. .NET Core was developed due mainly to the workloads found with ASP.NET core as well as the need to have further modernized runtime. It is the open source version of the .NET platform and includes many of the same APIs as found with the .NET framework. .NET Core is also cross platform so all of your developed applications can be run on Linux, macOS and Windows.