This page is an index to the Unix and Linux command tutorials and examples we've created. We've found that while Unix and Linux are powerful operating systems, its cryptic commands can sometimes be hard to remember, so hopefully these "Learn Unix by Example" tutorials will help make your Unix and Linux life easier.
File Management
The following commands are used to work with files and directories:
- cat
- "concatenate", used to display files, or concatenate files
- cd
- "change directory", used to move between directories
- chmod
- "change mode", lets you change file permissions
- chown
- "change owner", lets you change file ownership permissions
- compress
- used to compress files (this is an older command; see gzip or bzip2 for more modern approaches)
- cp
- used to copy files and directories
- file
- used to determine a file's "type"
- ls
- "list", list files and directories
- mkdir
- "make directory", used to create new directories
- more
- used to control the display of output, lets you page through the results
- mv
- "move", used to move files and directories
- pwd
- "print working directory", shows the directory you are currently in
- rm
- "remove", used to remove files and directories
- wc
- "word count", used to count characters, words, and lines in text files and/or standard input
Searching
The following commands are used to search files and directories:
- find
- a powerful command used to find files and directories with a wealth of search criteria
- grep
- "general regular expression parser", might be better named "search" or "textsearch"
- locate
- used to quickly find filenames anywhere on the file system
System Status
The following commands provide information about your Unix/Linux system:
- df
- "disk free", used to show information about free disk space on filesystems
- du
- "disk usage", most often used to determine the size of directories
- lsof
- list open files; typically used by system administrators to debug problems
- ps
- "process statistics", used to show the processes currently running on the system
- top
- a utility to show processes running, cpu usage, memory usage
- who
- show who is currently logged in
Text Processing
Unix and Linux text processing commands. Since their initial creation, Unix systems have been known as having powerful text processing commands.
- cut
- cut fields and columns from text output and files
- grep
- "general regular expression parser", might be better named "search" or "textsearch"
- sort
- used to sort information provided on standard input
- vi/vim
- vi/vim, the standard unix/linux text editor
- sed
- a "streamline editor", lets you edit files with commands, with no need for a text editor
Internet and Networking
You'll use these commands to work with networks and the internet from your Unix/Linux system:
- curl
- used to download web pages and other resources over the internet, from the command line (see wget)
- ping
- you can "ping" another computer to see if it is alive
- wget
- used to download web pages and other resources over the internet, from the command line (see curl)
Archives and Storage
This is a collection of tutorials about using Linux archives -- collections of files stored in one other file. The tar and gzip commands are the most popular commands today. The 'compress' command is included here for legacy reasons.
- compress
- used to compress files (older)
- tar
- "tape archive", create archives, and read/write from tapes and diskettes
- gzip
- used to compress files and archives (gunzip used to decompress them)
- bzip2
- also used to compress files
Printing
This is a collection of articles about Unix and Linux printing. (Note: I haven't used these commands since the 1990s, they may have changed quite a bit.)
- cancel
- used to cancel print requests
- lp
- "line printer"; used to submit print jobs
- lpstat
- "line printer statistics"; used to display information about printer queues
Miscellaneous
Here are a couple of "miscellaneous" commands. There are more that I need to document at some point:
- alias
- used to create new commands from existing commands
- crontab
- crontab is used to schedule unix/linux jobs to run at certain times
Unix/Linux shell script examples
Finally, here are links to just a few of our Unix and Linux shell script examples.