title: What are the advantages to using StringIO in Ruby as opposed to String?
body: <p>When is it considered proper to use Ruby's StringIO as opposed to just using String?</p>
  
  <p>I think I understand the fundamental difference between them as highlighted by "<a href="https://stackoverflow.com/questions/1211461/what-is-rubys-stringio-class-really">What is ruby&#39;s StringIO class really?</a>", that StringIO enables one to read and write from/to a String in a stream-oriented manner. But what does this mean practically?</p>
  
  <p>What is a good example of a practical use for using StringIO when simply using String wouldn't really cut it?</p>