title: What does "Content-type: application/json; charset=utf-8" really mean?
body: <p>When I make a POST request with a JSON body to my REST service I include <code>Content-type: application/json; charset=utf-8</code> in the message header. Without this header, I get an error from the service. I can also successfully use <code>Content-type: application/json</code> without the <code>;charset=utf-8</code> portion. </p>
  
  <p>What exactly does <code>charset=utf-8</code> do ? I know it specifies the character encoding but the service works fine without it. Does this encoding limit the characters that can be in the message body?</p>