title: What exactly does "Stream" and "Buffer" mean in Java I/O?
body: <p>I just learned about input/output using <code>BufferedReader</code>.</p>
  
  <p>I wanted to know what exactly are the meanings of the term <code>Stream</code> and <code>Buffer</code>?</p>
  
  <p>Also what does this line of code serves us:</p>
  
  <pre><code>BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
  </code></pre>