Twilio is a cloud communication platform that enables developers to build custom phone systems, including conference lines, with ease. By following Kyle Kelly-Yahner's step-by-step guide, users can create their own conference line using TwiML Bins, which are the building blocks of Twilio's API. With just a few minutes of effort, users can write code that responds to incoming calls, greets callers, and connects them to a conference call. By connecting this code to a phone number, users can test their conference line in real-time, making it easy for anyone to join a conference call without needing extensive coding knowledge.