In this article, Corey Weathers explains how to build a conference line using Twilio with ASP.NET Core and C#. The process involves setting up the developer environment, creating an API route to receive incoming calls, and connecting the app to Twilio. The article provides step-by-step instructions on how to create a basic conference call and offers suggestions for further development of the feature. To run the app, developers need to install the .NET Core SDK, Visual Studio Code, and the C# extension, as well as create an ASP.NET Core project and add the Twilio helper library. The article also mentions the use of ngrok to provide a URL that allows Twilio to reach the local machine. With this guide, developers can build their own conference line using Twilio and explore other features from the Conference TwiML documentation.