1.命令格式：
cd [目录名]2.命令功能
切换当前目录至 [目录名]
3. 常用范例
1.进入系统根目录
命令：
cd / 说明：进入系统根目录,上面命令执行完后拿ls命令看一下，当前目录已经到系统根目录了
输出：
hc@hc-virtual-machine:~$ pwd
/home/hc
hc@hc-virtual-machine:~$ cd /
hc@hc-virtual-machine:/$ ls
bin dev initrd.img lib64 mnt root snap sys var
boot etc initrd.img.old lost+found opt run srv tmp vmlinuz
cdrom home lib media proc sbin swapfile usr
pwd的作用是查询当前所在目录
2. 返回父级目录
命令：
cd ..输出：
hc@hc-virtual-machine:~/PycharmProjects$ pwd
/home/hc/PycharmProjects
hc@hc-virtual-machine:~/PycharmProjects$ cd ..
hc@hc-virtual-machine:~$ pwd
/home/hc3.进入当前目录的父目录的父目录
命令：
cd ../..输出：
hc@hc-virtual-machine:~/PycharmProjects$ pwd
/home/hc/PycharmProjects
hc@hc-virtual-machine:~/PycharmProjects$ cd ../..
hc@hc-virtual-machine:/home$ pwd
/home4. 进入当前用户主目录
“当前用户主目录”和“系统根目录”是两个不同的概念。进入当前用户主目录有两个方法。
命令1：
cd直接输入cd，然后回车
输出：
hc@hc-virtual-machine:~/PycharmProjects/my_test$ pwd
/home/hc/PycharmProjects/my_test
hc@hc-virtual-machine:~/PycharmProjects/my_test$ cd
hc@hc-virtual-machine:~$ pwd
/home/hc上面的命令是我在非root用户下操作的，现在我切换到root用户下再操作一遍
[email protected]:~/PycharmProjects/my_test$ sudo su
[email protected]:/home/hc/PycharmProjects/my_test# pwd
/home/hc/PycharmProjects/my_test
[email protected]:/home/hc/PycharmProjects/my_test# cd
[email protected]:~# pwd
/root命令2：
cd ~输出
hc@hc-virtual-machine:~/PycharmProjects/my_test$ pwd
/home/hc/PycharmProjects/my_test
hc@hc-virtual-machine:~/PycharmProjects/my_test$ cd ~
hc@hc-virtual-machine:~$ pwd
/home/hc5. 跳转到指定目录
命令
cd /home/hc/PycharmProjects/my_test/输出
hc@hc-virtual-machine:/$ pwd
/
hc@hc-virtual-machine:/$ cd /home/hc/PycharmProjects/my_test/
hc@hc-virtual-machine:~/PycharmProjects/my_test$ pwd
/home/hc/PycharmProjects/my_test6.返回进入此目录之前所在的目录
命令：
cd -说明：自动跳转到进入此目录之前所在的目录，并输出所在目录名称
输出：
hc@hc-virtual-machine:/$ pwd
/
hc@hc-virtual-machine:/$ cd /home/hc/PycharmProjects/my_test/
hc@hc-virtual-machine:~/PycharmProjects/my_test$ pwd
/home/hc/PycharmProjects/my_test
hc@hc-virtual-machine:~/PycharmProjects/my_test$ cd -
/
hc@hc-virtual-machine:/$ pwd
/7. 把上个命令的参数作为cd参数使用
命令：
cd !$输出:
hc@hc-virtual-machine:~/PycharmProjects/my_test$ pwd
/home/hc/PycharmProjects/my_test
hc@hc-virtual-machine:~/PycharmProjects/my_test$ ls /opt/
google
hc@hc-virtual-machine:~/PycharmProjects/my_test$ cd !$
cd /opt/
hc@hc-virtual-machine:/opt$ pwd
/opt