title: What is proc and sysfs entries
body: <p>I'd like to learn about <code>proc and sysfs entries</code>.</p>
  
  <p>So far, what I have understood is that, proc entries are the values which is set to proc file system. I'm not sure whether I'm correct. Could anyone explain it in detail about its real need and where it is used? Please provide me links to know it better. Any kind of guidance is accepted.</p>