These buttons control Disk Druid's actions. They are used to change the attributes of a partition (for example the file system type and mount point) and also to create RAID devices. Buttons on this screen are also used to accept the changes you have made, or to exit Disk Druid. For further explanation, take a look at each button in order:
Edit: Used to modify attributes of the partition currently selected in the Partitions section. Selecting Edit opens a dialog box. Some or all of the fields can be edited, depending on whether the partition information has already been written to disk.
RAID: Used to provide redundancy to any or all disk partitions. It should only be used if you have experience using RAID. To read more about RAID, refer to the Red Hat Enterprise Linux Deployment Guide.
To make a RAID device, you must first create software RAID partitions. Once you have created two or more software RAID partitions, select RAID to join the software RAID partitions into a RAID device.