Does PHP have to go along with SQL? : <p>I have been researching Sql, Django, PhP,</p>

<p>I saw this one tutorial on creating a social network website and they were using SQL in conjunction with PHP. Is this always required? What does the PHP do for the SQL? I know it is a server side, but isn't Django as well?
 So I can use Django/SQL instead of PHP/SQL?</p>
