Linux Environment

Gnome and the Bash shell are two of the most used interfaces in Linux for managing the system.

GNOME (GNU Network Object Model Environment, pronounced gah-NOHM) is a graphical user interface (GUI) and set of computer desktop applications for users of the Linux computer operating system. It's intended to make a Linux operating system easy to use for non-programmers and generally corresponds to the Windows desktop interface and its most common set of applications. In fact, GNOME allows the user to select one of several desktop appearances. With GNOME, the user interface can, for example, be made to look like Windows or like Mac OS. In addition, GNOME includes a set of the same type of applications found in the Windows Office product: a word processor, a spreadsheet program, a database manager, a presentation developer, a Web browser, and an e-mail program.

Here we will discuss shell more deeply since as a linux administrator or even a DBA using linux systems you would be expected to have a command on the shell inorder to undertake day to day activities.

The Linux shell provides a command line interface to the host environment and they're generally used to configure and manage Linux systems. Shell commands can be placed together in a script file and it can be run non interactively, which means they might be scheduled to run on a recurring basis and they can run in the background. Shells can execute commands and even start GUI-based applications. Linux systems come with one or more shells. Often, you might get two or three shells installed by default. But either way, you can add or remove shells at any point in time to your Linux installation. In Linux, the most common shell is Bash, which stands for Bourne Again Shell. Shells are sometimes also called command line interfaces or CLIs. But in the end, a shell is simply used to execute Linux commands.

Most shell commands are typed in, but there are a handful where most interactions are possible. Most shells will support advanced features like autocompletion, which is normally accomplished by pressing the Tab key using shortcuts, that means making links or creating aliases and using pipelines.On the shell command line, we can take the result of one command and pass it off or pipe it to the next command to the right. The Bourne Again shell or the Bash shell is by far the most common in Linux, but there are many others including the Korn shell, the Z shell, the C shell, and there are also others, such as the Scheme shell and the Friendly Interactive Shell, otherwise known as fish.

There are configuration files used by various shells. Some are read-only when connecting over the network to a Linux host and others only execute from a login shell. A login shell is when the user gets prompted for a username and password. A non-login shell by comparison is invoked. For example, in the graphical user interface, such as when a user starts a terminal session within the GUI.