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Linux an Overview

The majority of modern Linux distributions are user friendly, with a graphical user interface (GUI) that provides an easy way to perform common tasks. It is, however, quite different to both Windows and OS X, so to get the most out of your Raspberry Pi, you first need a quick primer on using the operating system.

As briefly explained in previous posts, Linux is an open source project that was originally founded to produce a kernel that was free for anyone to use. The kernel is the heart of an operating system, and it handles the communication between the user and the hardware.

Although it rightly refers only to the kernel, the term Linux is often used to refer to a collection of different open source projects from a variety of companies. These collections come together to form different flavours of Linux known as distributions.

The original version of Linux was combined with a collection of tools created by a group called GNU. The resulting system, known as GNU/Linux, was basic but powerful. Unlike many mainstream operating systems of the era, it offered facilities such as multiple user accounts in which several users share a single computer. Rival closed source operating systems have taken this system on board, with both Windows and OS X now supporting multiple user accounts on the same system. It’s also still present in Linux and provides security and protection for the operating system.

In Linux, you spend most of your time running a restricted user account. This doesn’t mean you’re limited in what you can do; instead, it prevents you from accidentally doing something that will break the software on your Raspberry Pi. It also prevents viruses and other malware from infecting the system by locking down access to critical system files and directories.

Before you can get started, it’s worth familiarising yourself with some of the terms and concepts used in the world of Linux, as defined in Table shown below. Even if you’re experienced with other operating systems, it’s a good idea to review this table before booting your Pi for the first time.

Terms/Concept Definition
Bash The most popular shell choice, used in the majority of Linux distributions.
Bootloader Software responsible for loading the Linux kernel. The most common is GRUB.
Console A version of the terminal that is always available, and the first thing you see on the Pi.
Desktop
Environment		 Software to make the GUI look pretty. GNOME and KDE are popular desktop environments.
Directory The Linux term for what Windows calls folders where files are stored.
Distribution A particular version of Linux. Pidora, Arch, and Raspbian are distributions.
Executable A file that can be run as a program. Linux files must be marked executable in order to run.
EXT2/3/4 The EXTended file system, the most common file system used in Linux.
File system The way a hard drive or other storage device is formatted so that it’s ready for file storage.
GNOME One of the most common Linux desktop environments.
GNU A free software project, which provides many of the tools used in Linux distributions.
GRUB The GRand Unified Bootloader, created by GNU and used to load the Linux kernel.
GUI A graphical user interface, in which the user operates the computer via a mouse or touch.
KDE Another extremely popular Linux desktop environment.
Linux Properly, the kernel used by GNU/Linux. Popularly, an open source operating system.
Live CD A Linux distribution provided as a CD or DVD which doesn’t require installation.
Package A collection of files required to run an application, typically handled by the package manager.
Package manager A tool for keeping track of and installing new software.
Partition A section of a hard drive that is ready to have a file system applied to it for storage.
root The main user account in Linux, equivalent to the Windows administrator account. Also called the superuser.
Shell A text-based command prompt, loaded in a terminal.
sudo A program that allows restricted users to run a command as the root user.sudo=superuserdo
Superuser see root
Terminal A text-based command prompt in which the user interacts with a shell program.
X11 The X Window system, a package that provides a GUI.
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