ASP.NET Core is Microsoft's modern, cross-platform, high-performance framework for building web applications, APIs, and microservices using C# and .NET. It runs on Windows, macOS, and Linux, offering a modular, lightweight architecture with built-in dependency injection, middleware pipelines, and unified MVC and Web API development. Key to success with ASP.NET Core is understanding that it separates concerns through middleware (request pipeline), filters (MVC-specific logic), and services (dependency-injected components), enabling both traditional MVC apps with Razor views and modern REST APIs with Minimal APIs or controllers. The framework integrates seamlessly with Entity Framework Core for database access and supports modern patterns like SignalR for real-time communication and gRPC for high-performance RPC.

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