Scripting VoiceXML and TwiML using Tcl

This article describes how to write XML-based programmable scripts such as for W3C's VoiceXML or Twilio's TwiML using Tcl, the Tool Command Language. The associated project is available as open source software at
  1. How easy is a programming language?
  2. What is Tcl?
  3. What are XML-based documents?
  4. How do I get started?