The output will be what you expect, it will echo Hello World onto the screen. You can also use echo to view the contents of a variable: As with most Linux commands, there's definitely more that we can ...

It's easy to add a few lines of text to files on Linux, but there are tools that make it easier to add many lines. There are a number of ways to add text to files on Linux systems without having to ...

There are three facts we can use to our advantage: The option variable ("optvar") stores the option name currently being ...

Linux might sound scary for first-time Linux users, but actually, it isn’t. Linux is a bunch of open-source Unix operating systems based on Linux Kernel. These operating systems are called Linux ...

Learn how to append text to files in Linux using commands like double redirection operator, tee, and sed without overwriting existing data.

Linux is often regarded as a complex operating system. In fact, even though it’s free, some experts argue that there’s a DIY ...

This article is reprinted from the book A Practical Guide to Linux Commands, Editors, and Shell Programming 3rd edition, with permission of the author and publisher ...