“Razor Pages are a new feature in ASP.NET Core 2.0. They provide a simpler way to organize code within ASP.NET Core applications, keeping implementation logic and view models closer to the view implementation code. They also offer a simpler way to get started developing ASP.NET Core apps, but that doesn’t mean you should dismiss them if you’re an experienced .NET developer. You can also use Razor Pages to improve the organization of larger and more complex ASP.NET Core apps.”
Source: ASP.NET Core – Simpler ASP.NET MVC Apps with Razor Pages