Partitioning = You can split every disk into one ore more parts, which are called 'partitions'. This is useful if you want to seperate your data or if you want to encrypt only a part of your disk.
SelectDevice = Choose one of the disks given in the list. Be aware that you lose all data on the partitions of this disk if you confirm this action later.
PartMode = You may choose between 'automatic' and 'manual' partitioning. Automatic partitioning creates only one partition for the whole disk. With manual partition you can split the disk into multiple parts of different size.
PartitionList = Choose a size for your partitions and add it to the list by clicking on the corresponding button. You may remove any partition later. Nothing will get written to your disk until you click on the 'write partition table' button. Be very careful as you destroy all data on this disk.