.... If there are more then one such disk of the same size, it makes RAID array. Separate partitions are used for /boot, and /, and logical volumes for /usr, /var, /tmp and /home. Only minimal disk space are allocated. You should expand (may be done online) logical volumes and file systems when You need to get more disk space. Also there are option to install system into single pre-mount point. In this case partitioning and mounting every part leave on Your own.