The Twilio.TwiML helper library simplifies the process of creating TwiML by providing a set of simple methods that generate TwiML elements and attributes, freeing developers from manually creating well-formed XML responses. The library allows for fluent method chaining to create complex TwiML flows, and supports hosting on publicly accessible URLs to test Twilio requests. The library is designed to be used with ASP.NET applications, providing a set of utilities that make it easy to work with TwiML and Twilio Client.