格式：mount [-t 文件系统类型] 挂什么设备 挂哪里
挂载设备，可以供系统随机存取数据的接口设备，b类型。
查看了一下系统中b类型文件，有md hd fd loop sd ram 。
可以挂载的文件系统：
iso9660 光盘或光盘镜像
msdos DOS 文件系统
vfat Windows 9x 文件系统
ntfs Windows NT
smbfs Mount Windows文件网络共享
nfs UNIX(Linux) 文件网络共享
df -l 可以查看挂载情况。
blkid 可以查看存储设备id。
lsblk 作用大概同上吧，我的CentOS 5.8 没有这个命令。
挂载目录中，之前存在的文件，在此目录挂载设备后，原来的文件不见了，此目录是挂载后新挂载设备中的文件。接挂后，原来目录中的文件又自行出现。
参考：
mount
Usage: mount -V : print version
mount -h : print this help
mount : list mounted filesystems
mount -l : idem, including volume labels
So far the informational part. Next the mounting.
The command is `mount [-t fstype] something somewhere‘.
Details found in /etc/fstab may be omitted.
mount -a [-t|-O] ... : mount all stuff from /etc/fstab
mount device : mount device at the known place
mount directory : mount known device here
mount -t type dev dir : ordinary mount command
Note that one does not really mount a device, one mounts
a filesystem (of the given type) found on the device.
One can also mount an already visible directory tree elsewhere:
mount --bind olddir newdir
or move a subtree:
mount --move olddir newdir
One can change the type of mount containing the directory dir:
mount --make-shared dir
mount --make-slave dir
mount --make-private dir
mount --make-unbindable dir
One can change the type of all the mounts in a mount subtree
containing the directory dir:
mount --make-rshared dir
mount --make-rslave dir
mount --make-rprivate dir
mount --make-runbindable dir
A device can be given by name, say /dev/hda1 or /dev/cdrom,
or by label, using -L label or by uuid, using -U uuid .
Other options: [-nfFrsvw] [-o options] [-p passwdfd].
For many more details, say man 8 mount .