Почему мой & ldquo; sudo fdisk -l & rdquo; выходной такой грязный?

Как я могу это исправить, и это даже проблема.

sudo fdisk -l

Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x000c5518

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048      499711      248832   83  Linux
/dev/sda2          501758  1953523711   976510977    5  Extended
Partition 2 does not start on physical sector boundary.
/dev/sda5          501760  1953523711   976510976   8e  Linux LVM

Disk /dev/sdb: 8012 MB, 8012390400 bytes
24 heads, 9 sectors/track, 72450 cylinders, total 15649200 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000437

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb2            2048    15648767     7823360    5  Extended
/dev/sdb5          501760    15648767     7573504   8e  Linux LVM

Disk /dev/mapper/Joseph--Debian-root: 7381 MB, 7381975040 bytes
255 heads, 63 sectors/track, 897 cylinders, total 14417920 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/mapper/Joseph--Debian-root doesn't contain a valid partition table

Disk /dev/mapper/Joseph--Debian-swap_1: 369 MB, 369098752 bytes
255 heads, 63 sectors/track, 44 cylinders, total 720896 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/mapper/Joseph--Debian-swap_1 doesn't contain a valid partition table

Disk /dev/mapper/xubuntu--vg-root: 991.4 GB, 991399247872 bytes
255 heads, 63 sectors/track, 120530 cylinders, total 1936326656 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x00000000

Disk /dev/mapper/xubuntu--vg-root doesn't contain a valid partition table

Disk /dev/mapper/xubuntu--vg-swap_1: 8497 MB, 8497659904 bytes
255 heads, 63 sectors/track, 1033 cylinders, total 16596992 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x00000000

Disk /dev/mapper/xubuntu--vg-swap_1 doesn't contain a valid partition table

Я определенно новичок и привыкла к гораздо более простому выводу. Что такое диск / dev / mapper? Я никогда не видел этого раньше, и видел только сейчас с новой установкой Xubuntu поверх Ubuntu-Gnome edition Благодаря.