The shell is a programming language. Don’t let anyone tell you otherwise. The shell is not just glue that
sticks bits together. The shell is a lot more than a tool that runs other tools. The shell is a complete
programming language!
When a Linux user asked me about membership databases, I asked him what he really needed. He
wanted to store names and addresses for a couple of hundred members and print mailing labels for each
of them. I recommended using a text editor to store the information in a text file, and I provided a shell
script to create the labels in PostScript.