Web API request and response are transmitted over the internet (HTTP-based data transfer). Network bandwidth is precious, it varies across regions. Web API responses are mostly in JSON form (a lightweight collection of strings). In these cases, even if we are sending a huge amount of data, it does matter a lot.
For quick transfer of response data over HTTP, it's good to compress the response before returning to clients. ASP.NET Core provides Response Compression Middleware, which compresses the response before sending it to clients.
Let's see it action, create PersonController with returns list of Person over the GET request (you can still continue using any Web API project from the book). I am using GenFu--the NuGet package to generate realistic prototype data, install this package or we can even connect to the database and return response of any table...