title: Difference betweeen RFC 3548 and RFC 4648
body: <p>I am translating some <code>Python</code> code to <code>C++</code>. Parts of the code use <code>base 64 encoding.</code> </p>
  
  <p>The <code>Python code</code> uses <code>RFC 3548 encoding</code>, but the <code>C++ library</code> I am using only has <code>RFC 4648</code>.</p>
  
  <p>I understand that <code>RFC 4648</code> obsolete <code>RFC 3548</code>, but I could not find out where they differ. I also wrote a program in Python and one in C++ to encode the same plain-text file, and they produce the same output.</p>
  
  <p><strong>So for base 64 encoding, what are the differences between RFC 3548 and 4648?</strong></p>