ASP.NET and ASP.NET MVC4

ASP.NET is the actual underlying framework for web development. It is built over .NET framework, and you can use C# and/or VB.NET to develop your web applications. You can think of it as a platform, for build web-based applications. ASP.NET itself consists of multiple sub-frameworks, best suitable for different type of websites, starting and ranging from personal blogs, to enterprise websites. Common sub-frameworks are, 

1. ASP.NET Web Pages 
2. ASP.NET Web Forms
3. ASP.NET MVC
4. ASP.NET SignalR
5. ASP.NET Single Page Applications

And quite other libraries too. You should note that Web Pages is to be engulfed by ASP.NET's next version, and MVC will take over. 


Now, talking about the difference. You should know that ASP.NET is the actual underlying framework, the MVC is just an architect for building the applications over ASP.NET. It consists of three sections, 

1. Model - for data
2. View - for HTML web pages
3. Controller - for actual back-end code. 

It makes the web application much more efficient and simpler. ASP.NET can run, without implementing the MVC framework, but MVC architecture won't run without ASP.NET being the underlying framework. 


If you want to learn the ASP.NET MVC framework, you can refer this article of mine and learn the framework; programming and the concepts.