Shell (computing)

In computing, a shell is a user interface for access to an operating system's services. In general, operating system shells use either a command-line interface (CLI) or graphical user interface (GUI), depending on a computer's role and particular operation.

The design of a shell is guided by cognitive ergonomics and the goal is to achieve the best workflow possible for the intended tasks; the design can be constricted by the available computing power (for example, of the GPU) or the available amount of graphics memory. The design of a shell is also dictated by the employed computer periphery, such as computer keyboard, pointing device (a mouse with one button, or one with five buttons, or a 3D mouse) or touchscreen, which is the direct human–machine interface.

CLI shells allow some operations to be performed faster in some situations, especially when a proper GUI has not been or cannot be created. However, they require the user to memorize commands and their calling syntax, and also to learn the shell-specific scripting language, for example bash script. CLIs are also easier to be operated via refreshable braille display and provide certain advantages to screen readers.

Shell

Shell may refer to:

Architecture and design

Business

Chemistry and Physics

Computing

Command-line interface

A command-line interface or command language interpreter (CLI), also known as command-line user interface, console user interface, and character user interface (CUI), is a means of interacting with a computer program where the user (or client) issues commands to the program in the form of successive lines of text (command lines).

The CLI was the primary means of interaction with most computer systems until the introduction of the video display terminal in the mid-1960s, and continued to be used throughout the 1970s and 1980s on OpenVMS, Unix systems and personal computer systems including MS-DOS, CP/M and Apple DOS. The interface is usually implemented with a command line shell, which is a program that accepts commands as text input and converts commands to appropriate operating system functions.

Command-line interfaces to computer operating systems are less widely used by casual computer users, who favor graphical user interfaces.

Alternatives to the command line include, but are not limited to text user interface menus (see IBM AIX SMIT for example), keyboard shortcuts, and various other desktop metaphors centered on the pointer (usually controlled with a mouse). Examples of this include the Windows versions 1, 2, 3, 3.1, and 3.11 (an OS shell that runs in DOS), DosShell, and Mouse Systems PowerPanel.

Windows Server

Windows Server is a brand name for a group of server operating systems released by Microsoft. It includes all Windows operating systems branded "Windows Server", but not any other Microsoft product. The first Windows server edition to be released under that brand was Windows Server 2003. However, the first server edition of Windows was Windows NT 3.1 Advanced Server, followed by Windows NT 3.5 Server, Windows NT 4.0 Server, and Windows 2000 Server; the latter was the first server edition to include Active Directory, DNS Server, DHCP Server, Group Policy, as well as many other popular features used today.

Members

This brand includes the following operating systems:

Microsoft has also produced Windows Server Essentials (formerly Windows Small Business Server) and Windows Essential Business Server (discontinued), software bundles which includes a Windows Server operating system and some other Microsoft Servers products.

Graphical user interface

In computer science, a graphical user interface or GUI, pronounced /ˈɡuːi/ ("gooey") is a type of interface that allows users to interact with electronic devices through graphical icons and visual indicators such as secondary notation, as opposed to text-based interfaces, typed command labels or text navigation. GUIs were introduced in reaction to the perceived steep learning curve of command-line interfaces (CLIs), which require commands to be typed on the keyboard.

The actions in a GUI are usually performed through direct manipulation of the graphical elements. In addition to computers, GUIs can be found in hand-held devices such as MP3 players, portable media players, gaming devices, smartphones and smaller household, office and industrial equipment. The term "GUI" tends not to be applied to other low-resolution types of interfaces with display resolutions, such as video games (where HUD is preferred), or not restricted to flat screens, like volumetric displays because the term is restricted to the scope of two-dimensional display screens able to describe generic information, in the tradition of the computer science research at the PARC (Palo Alto Research Center).