The video tutorial covers the ASP.NET Core 3.1 series, focusing on the new project file structure, program and startup files, Razor pages, and the request-response flow. It explains the trimmed project file, the role of the program and startup files in configuring services and middleware, and the use of Razor pages for HTML responses. The tutorial also details the request-response flow through the ASP.NET Core server, highlighting the routing middleware and page handler methods.

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