In ASP.NET Core, middleware components are like building blocks that process HTTP requests and responses. When a request reaches the server, it passes through each middleware one by one. Each middleware can do something with the request (like check authentication or log information) and then either pass it to the next component or stop the pipeline if it can fully handle the request. Similarly, when the response comes back, it passes through the same middleware in reverse order, allowing each component to modify the response before it reaches the client.

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