title: CATALINA_HOME path set up
body: <p>During installation of Tomcat, multiple forums have that CATALINA_HOME variable needs to be set up and shall point to Tomcat parent directory. I am running web projects through eclipse and it runs in presence and also in absence of this environment variable set up.  </p>
  
  <p>I wish to know what exact purpose does this variable solve and when does setting it up become mandatory.  </p>
  
  <p>Also I wish to know the exact use of tomcat-juli.jar that resides in the Tomcat/bin directory</p>