table of Contents
- 1. -h, --help, man command help
- 2. sudo command to run as administrator
- 3. apt-get install software
- 4. apt-cache show to see a piece of software
- 5. apt-cache search search for a software
- 6. dpkg through local installation file
- 7. date operating system date (see Review)
- 8. cal calendar action
- 9. tzselcet time zone selection
- 10.passwd Change Password
1. -h, --help, man command help
格式：
command -h
command --help
info command
man command
Format: man -f passwd
fuzzy match
Format: man -k passwd