title: How do uppercase and lowercase letters differ by only one bit?
body: <p>I have found one example in Data and Communication Networking book written by Behrouza Forouzan regarding upper- and lowercase letters which differ by only one bit in the 7 bit code.</p>
  
  <blockquote>
    <p>For example, character <code>A</code> is 1000001 (0x41) and character <code>a</code> is 1100001 (0x61).The difference is in bit 6, which is 0 in uppercase letters and 1 in lowercase letters.  If we know the code for one case, we can easily find the code for the other by adding or subtracting 32 in decimal, or we can just flip the sixth bit.</p>
  </blockquote>
  
  <p>What does all this mean?</p>
  
  <p>I have found myself very confused with all these things.  Could someone provide examples of how these things really work out?</p>