title: What is an example of a non utf-8 character(not the codepoint)?
body: <p>I'm trying to test my code to make sure it only accepts utf-8 characters. The user is able to send a name as input and i want to make sure this name is not anything other that utf8. </p>
  
  <p>I know that you can build a non utf8 character in the binary format but as far as I know the user can't send the input in the binary format. what is an example of a character that user can type in that is not supported in utf-8.</p>
  
  <p>BTW I'm writing my code in php and the default encoing is utf-8.</p>