pwd:显示当前所在目录
~：root目录
/：根目录
ls：查看当前目录下所有的文件和目录
cd usr 切换到该目录下usr目录
cd?../ 切换到上一层目录
cd / 切换到系统根目录
cd?~ 切换到用户主目录
cd - 切换到上一个所在目录（返回）
?
栗子
[email?protected]:~/RK3288_Lakala/kernel/arch/arm/boot/dts$ cd -
/home/yangw
[email?protected]:~$ pwd
/home/yangw
[email?protected]:~$ cd -
/home/yangw/RK3288_Lakala/kernel/arch/arm/boot/dts
[email?protected]:~/RK3288_Lakala/kernel/arch/arm/boot/dts$ pwd
/home/yangw/RK3288_Lakala/kernel/arch/arm/boot/dts
[email?protected]:~/RK3288_Lakala/kernel/arch/arm/boot/dts$ cd ~
[email?protected]:~$ pwd
/home/yangw
[email?protected]:~$ cd /
[email?protected]:/$ pwd
/
[email?protected]:/$ cd -
/home/yangw