Security is of course an integral part of any application. It is usually designed as part of the abstract application framework during the design phase. There are many different aspects of security in a web application, and most developers, especially network administrators focus on the unknown public portion of security when it comes to design.
You can have firewalls, IP filtering, load balancing, DMZ’s and more when it comes to physical infrastructure with security. Keeping hackers and the general public out of private information and sensitive servers is of course one of the biggest security concerns.
The type of security this tutorial refers to however, is regarding internal user access security. Aside from the obvious security concerns already mentioned, there is often a definite hierarchy of privilege in any company. The different types of users that make up an application can be many. From administrators, so supervisors, to department managers, to regular field workers, all of whom require different levels of security access in your application.