The truth about Linux today is that one may never have to actually touch a terminal or issue a single Linux command in order to run some versions of this flexible alternative operating system. But once a user becomes accustomed to using the command line interface, it soon becomes the preferred method in many tasks.

The reason people go for an operating system like Linux is the sum of its parts—its total usefulness. It is stable, affordable, fast, and runs on all kinds of hardware. It is also extremely flexible right out of the box, largely because of its powerful command-line interface (CLI), or shell.

Like all Linux distributions, Ubuntu 10.10, aka, Maverick Meerkat, the latest version of the popular Linux distribution, ships with a firewall installed. The firewall is actually embedded in the kernel. In Ubuntu, the firewall’s original command line interface has been replaced by ufw, a more user-friendly command line script.

I thought it would be useful to break away from all the GUI-goodness and offer up a few command line tips and tricks. Why? No matter how powerful, user-friendly, and modern the Linux desktop becomes, there may come a time when you want to step up your game and get down and dirty with the command line interface.

Today’s “Newbie Tip” is learning some basics about the “Command Line Interface” or as it’s mostly referred to, “Command Line”. The command line gives the user the ability to interact with the operating system by typing via a text terminal.

I am not a text mode Luddite. I use a graphical user interface (GUI) every day. However, for certain tasks a GUI is just not the best choice.

One of the most powerful features of the Linux command line interface, (and other shells that conform to the POSIX standard) is the ability to pipeline output from one command as the input to another. This is done using the vertical bar or pipe character [ | ].

One of the biggest complaints about Linux®, particularly from developers, is the speed with which Linux boots. By default, Linux is a general-purpose operating system that can serve as a client desktop or server right out of the box. Because of this flexibility, Linux serves a wide base but is suboptimal for any particular configuration.

ufw, the Uncomplicated FireWall, is Ubuntu’s user-friendly, command line frontend to IPTables, the command line utility for managing Netfilter, the firewall application built into the Linux kernel. It is installed not just on Ubuntu, but also on all Ubuntu-based distributions. As simple to use as ufw is, a graphical interface is even better, especially for new users.