For Legend look here

Basic Information Commands

1. Output date and time of system:

   1. Predefined format

      date
      # Output depends on Locale Settings

   2. Given format:

      date +%F_%T
      # 2020-01-06_14:30:00 

2. Information about user:

   1. Current user:

      id
      # uid=1003(zasher) gid=985(users) groups=985(users)

   2. Get list of logged in users:

      who
      # zasher    tty1    Jan 6 13:35

3. Uptime of System:

   uptime
   # 14:44:22 up 24 days, 23:34, 0 users, load average: 0,33, 0,33, 029

4. Read Manual about a command:

   man 
   
   # Hint: Uses the program specified as $PAGER to display the manual

5. Find manuals for containing a word in its name:

   apropos 

6. Log out:

   exit

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