title: How to replace character 'a' with 'b' and 'b' with 'a' in a string?
body: <p>Suppose I have the following string.</p>
  
  <blockquote>
    <p>blaah blaah blaah blaah</p>
  </blockquote>
  
  <p>the resulting string should be:</p>
  
  <blockquote>
    <p>albbh albbh albbh albbh</p>
  </blockquote>
  
  <p>Is there any built in method in JavaScript to find and replace a character like this in a string?</p>