A Unix script is a program which is written in a programming language built into one of the Unix shells.

If you can type commands into the Unix shell, you can write a shell script. A shell script can be as simple as a text file containing a list of commands.

Let’s say that you frequently FTP to the server ftp.ox.ac.uk. You could create a Unix script called “ox” to FTP to that server automatically. This would save you typing everytime you connected.

Your simple Unix script could contain just this one line:

ftp ftp.ox.ac.uk

You could then execute your script by using the command “sh ox”, or you could set the file permissions of the script to allow it to be executed by typing just “ox”.