Command Reference

For many of these commands, you will find more information by typing
man [command]
at the UNIX command line.

General UNIX commands

  1. ls -- (List Schema) This command will list the contents of your current directory. It only returns files that are not (.) "dot" files.
  2. mkdir -- (Make Directory). With this command will create a subdirectory in your home directory.
  3. cd - (Change Directory) With this command you can move from your current working directory to a new directory.
  4. pwd -- (Print Working Directory). The pwd command, when evoked, will display the absolute pathname for the directory you are currently in..
  5. cp (copy). This command will copy a file from one directory to another.
  6. mv -- (Move) this allows you to move a file from one place to another
  7. rm - (Remove) This command is used to delete a file.
  8. rmdir (Remove Directory) This command is used to delete directories.
  9. clear - Clear the terminal window.
  10. cat (Concatenate) Can be used to display the contents of a file on the screen.
  11. more -- The more command is used to view files just like cat except that the more command lets you view the information 1 page at a time.
  12. head -- The head command writes the first 10 lines of a file to the screen.
  13. tail -- The tail command writes the last ten lines of a file to the screen.
  14. grep -- The grep command will search a file for specified words or patterns and prints out each line in which the word or pattern occurs.
  15. wc -- (Word Count) this gives a word count for a specific filename.
  16. ping -- allows to determine if a hosts Ethernet configuration is good.
  17. traceroute -- allows you see the path that a packet must travel to get to its destination.
  18. ns lookup -- allows you to invoke DNS to lookup a host or IP address.
  19. .whois -- Script that Queries the InterNic Database for information on a particular host.
  20. chmod -- Change access modes on files.
  21. csplit -- Break files at specific locations.
  22. file -- Determine a files type.
  23. install -- Set up system files.
  24. ln -- Create filename aliases.
  25. rcp -- Copy files to a remote system.
  26. split -- Splits files evenly.
  27. banner -- Make posters from words.
  28. pc -- Precision Calculator.
  29. cal -- Display Calendar.
  30. calendar -- Check for reminders.
  31. kill -- Terminate a running command.
  32. nice -- Reduce a jobs priority.
  33. nohup -- Preserve a job after logging out.
  34. passwd -- Set a password.
  35. script -- produce a transcript of your login session.
  36. spell -- report misspelled words.
  37. su -- Become a superuser.

Printing commands

  1. cancel -- Cancel a printer request.
  2. lp -- Send to the printer.
  3. lpstat -- Get printer status.
  4. pr -- Format and paginate for printing.


  1. egrep -- Extended version of grep.
  2. fgrep -- Search files for literal words.
  3. find -- Search the systems for filenames.
  4. grep -- Search files for text patterns.
  5. strings -- Search binary files for text patterns.

Shell Programming

  1. echo -- Repeat input on the output.
  2. expr -- Perform arithmetic and comparisons.
  3. line -- Read a line of input.
  4. sleep -- Pause during processing.
  5. test -- Test a condition.


  1. compress -- Compress files to free up space.
  2. cpio -- Copy archives in or out.
  3. pack -- Pack files to free up space.
  4. pcat -- Display contents of packed files.
  5. tar -- Tape archiver.
  6. uncompress -- Expand compressed (.Z) files.
  7. unpack -- Expand packed (.z) files.
  8. zcat -- Display contents of compressed files.

System Status

  1. at -- Execute commands later.
  2. chgrp -- Change file group.
  3. chown -- Change file owner.
  4. crontab -- Automate commands.
  5. date -- Display or set date.
  6. df -- Show free disk space.
  7. du -- Show disk usage.
  8. env -- Show environmental variables.
  9. finger -- Point out information about users.
  10. ps -- Show processes.
  11. ruptime -- Show loads on working systems.
  12. shutdown -- Revert to single-user mode.
  13. stty -- Set or display terminal settings.
  14. who -- Show who is logged on.

Text Processing

  1. cut -- Select columns for display.
  2. ex -- Line-editor underlying vi.
  3. fmt -- produce roughly uniform lines.
  4. fold -- Produce exactly uniform line lengths.
  5. join -- Merge different columns into a database.
  6. nawk -- New version of awk.
  7. paste -- Merge columns of switch order.
  8. sed -- Noninte4active text editor.
  9. sort -- Sort or merge files.
  10. tr -- Translate characters.
  11. uniq -- Find repeated or unique lines in a file.
  12. vi -- Visual editor.
  13. xargs - Process many arguments in a manageable portions.

Test Yourself

Think that you know your basic UNIX commands? Do you now how to remove a directory with files in it? Why not take our Unix Commands Quiz and see where you're at?