First of all, you should know that rooting is not an official process it is not allowed especially for Samsung devices. This is an unofficial operation which is actually not supported by Samsung devices and you may lose your phone warranty
Though it is an unofficial process but after this process, you will be able to follow the following. You can remove bloatware, You can install apps other than from google play, You can Install custom recovery images, You can take backup with the non-android application. You can install custom ROM’s and you can do a lot more .