Arduino IDE is not just another IDE, it's totally necessary if you work with arduino boards. Before Arduino IDE was really difficult to deal with the drivers, ports and code, so in Windows as in Linux. With this IDE you can search which board you are using and which libraries you want to link and Arduino IDE do the rest.

Arduino IDE it's a simple application that allows you to develop arduino applications with the help that gives a IDE. It format the code to make it simple, and connect with the board compatibles to upload the code.

Arduino IDE is an IDE very similar to Eclipse and NetBeans, specially defined to work with Arduino boards. You can add all the libraries that you needs very easy, including third party libraries, it's fast to do it. Also this program includes all drivers that you can need to use the different flavors of Arduino boards