title: What is InputStream & Output Stream? Why and when do we use them?
body: <p>Someone explain to me what <code>InputStream</code> and <code>OutputStream</code> are?</p>
  
  <p>I am confused about the use cases for both <code>InputStream</code> and <code>OutputStream</code>.</p>
  
  <p>If you could also include a snippet of code to go along with your explanation, that would be great. Thanks!</p>