How to install EPEL Repository on RHEL/CentOS 7.x/6.x/5.x

This is "How To" guide to show us, how one can configure RHEL/CentOS system to use Extra Packages from EPEL repository. After enabling the EPEL repository, one can easily install standard open source packages and their dependencies by using YUM command.  

In this article, we would discuss below points:
What is EPEL?
Why one should use EPEL repository?
How To enable EPEL repository on RHEL/CentOS 7/6/5?
How To verify if EPEL repository is enabled or not?
How To use EPEL repository?

Is Tomcat a web server or an application server?

Tomcat is a web server (handles HTTP requests/responses) and web container (implements Java Servlet, JavaServer Pages, Java Expression Language and Java WebSocket technologies) if we don't consider that we have all the add-ons and plugins made available through open source or commercially with Tomcat. Tomcat doesn't implement the complete Java EE API and doesn't have EJB container. Although we could run some applications in Tomcat(one could easily argue that it is an application server) it will not be considered as a full-fledged application server as it lacks some features of the application server.

Conclusion:
One could develop many applications on top of Tomcat with pluggable services and add-ons. If Tomcat + add-ons + pluggable services then we can call it an Application Server.

Thank you for reading this article. Hope you would like it. If you have any suggestion or have any question do let me know in the comment box. Happy Learning!!😌