為什么我這里的硬盤顯示的是xvda？這個是什么意思

[root@iZ28lmffy00Z /]# fdisk -l

Disk /dev/xvda: 42.9 GB, 42949672960 bytes, 83886080 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 label type: dos

Disk identifier: 0x0009e68a

? ? Device Boot ? ? ?Start ? ? ? ? End ? ? ?Blocks ? Id ?System

/dev/xvda1 ? * ? ? ? ?2048 ? ?83884031 ? ?41940992 ? 83 ?Linux