ASP.NET Core MVC is a web framework, built on top of the core .NET framework, specifically made for building efficient web applications and APIs that will be able to be reached by a massive range of clients including web browsers, mobile devices, smart TVs, web-based home automation tools, and more.

Angular 2 is the second major installment of AngularJS, a world-renowned development framework born with the idea of giving the coder the toolbox needed to build reactive, cross-platform web-based apps, which are optimized for desktop and mobile: it features a structure-rich templating approach which is based upon a natural, easy-to-write, and readable syntax.

These two frameworks were put together with the same assumption in mind: the HTTP protocol is not limited to serving web pages, it can be also used as a viable platform to build web-based APIs to effectively send and receive data. This theory has slowly made its way through the first 20 years of the World Wide Web and is now an undeniable, widely acknowledged statement, and also a fundamental pillar of almost every modern web development approach.

As for the reasons behind this perspective switch, there are plenty of good reasons for it, the most important of them being related to the intrinsic characteristics of the HTTP protocol. It is simple to use, flexible enough to match most development needs in the always-changing environment which the World Wide Web happens to be, not to mention how universal it has become nowadays, almost any platform that you can think of has an HTTP library, so HTTP services can reach a broad range of clients, including browsers, mobile devices, and traditional desktop applications.