ASP.NET Core 2 combines ASP.NET MVC and WebAPI into a single framework and enhances features like modular architecture, environment-based configurations, and built-in dependency injection. It supports cross-platform development on various operating systems and excels in performance and scalability, making it ideal for microservices and high-speed applications. Side-by-side deployments allow multiple .NET versions on the same server, facilitating smoother application upgrades.