In computer science is called Shell the software that connects the user to the computer. The shell allows for example to use kernel services and to obtain information about system components or to use it. The term "Shell" (English for "envelope" or " shell " ) comes from shells and describes an interface between the user and the interior ( the kernel components ).
In operating systems, there are two types of shells, the command line ( english Command Line Interface CLI) and graphical user interfaces (English Graphical User Interface GUI). However, the command line interpreter is meant as a shell in the vernacular often. For the operating systems Unix / Linux see Unix shell.
Modern versions of Microsoft Windows using the Windows Explorer, offering a working environment with Start Menu and Taskbar. The older Windows 3.x, however, used the program manager, which differed from today's desktop concept. In various versions of the DOS command line interpreter dominates as a shell.
The graphical shell of Mac OS is the finder; he was part of the first operating system version in 1984 and is also available on the current system versions.
With Windows 7 and Windows Server 2008, Microsoft introduced the Windows PowerShell, is to provide a useful tool for system administration the administrators. The Windows PowerShell recalls the work with the Unix shell.