One-page Introduction to Unix

Unix is an operating system, meaning you can use it to organize files and directories and to start up applications, such as a browser or a text editor.

In unix, like many other operating systems, directories can store files and other directories. In this way, you can make a “tree” shape out of directories. The top-most directory is your home directory; you will already have one existing subdirectory named “ucwise”. You will need to create more subdirectories, within “ucwise”, to contain homework files, and so forth.

Directory commands:

mkdir arg

Make a new subdirectory (folder) named arg

rmdir arg

Remove the directory named arg. (Directory must be empty)

cd arg

Move to the directory named arg, which should be a subdirectory of the current directory.

cd ..

Move to the directory containing the current one (i.e., move “up” a directory)

cd ~

Move to your home directory


Show a listing of the contents of the current directory

ls -l

Get a long listing of the directory

File commands:

cp old new

Make a new file, called new, which is a copy of the existing file old.

rm arg

Remove (delete) the file named arg.

rm *

Remove all the files in the current directory (yikes!)

mv old new

Change the name of the file from old to new.

Applications (using programs):


Startup the Firefox browser (the “&” means that you will be able to use you unix window even while Firefox is running).


Start up the emacs editor

emacs file

Use emacs to edit the file named file


Start up the scheme programming environment STk directly. Usually, though, you will use STk inside emacs.

submit assg

Submit the assignment named assg. The submit program will try to find the proper files in the current directory.

For further information, see