Model–view–controller (MVC) is a software architectural pattern for implementing user interfaces on computers. It divides a given application into three interconnected parts. This is done to separate internal representations of information from the ways information is presented to, and accepted from, the user.
ASP.NET MVC 4 is the latest version if you are using .NET 4. ASP.NET MVC 5 is the latest version if you are using .NET 4.5.x. MVC 6 in beta and will be shipped in future. The Lib.Web.Mvc 6.0.1 does not look part of ASP.NET MVC Packages.