- pwd:print work directory
 - ps:process status
 - df:disk free
 - du:disk usage
 - cat:concatenate 连锁,连接
 - insmod:install module 载入模块
 - ln -s:link -soft 创建一个软链接,相当于创建一个快捷方式
 - mkdir:make directory
 - touch:触碰,用于创建空文件与修改时间戳
 - man:manual 使用手册
 - su:swith user(切换用户)
 - cd:change directory
 - ls:list files
 - mkdir:make directory
 - rmdir:remove directory
 - mkfs:make file system
 - fsck:file system check
 - uname:Unix name
 - lsmod:list modules
 - mv:move file
 - rm:remove file
 - cp:copy file
 - ln:link files
 - fg:foreground
 - bg:background
 - chown:change owner
 - chgrp:change group
 - chmod:change mode
 - umount:unmountv 卸载
 - tar:tape archive 磁带档案
 - ldd:list dynamic dependencies
 - insmod:install module
 - rmmod:remove module
 - lsmod:list module
 - rpm:red hat package manager
 - dpkg:debian package manager
 - apt:advanced package tool debian或基于debian的发行版中提供