ASL STEM

Definition

a program that accepts operating system commands and causes them to be executed. For example, when you type a command such as dir, the command is read by the shell. The Windows shell is called command prompt or ms-dos prompt and is derived from command.com, which was part of DOS. UNIX users have a choice of shells, such as the C shell (csh), the Bourne shell (sh), and the Korn shell (ksh).

Source: Downing, Douglas, et al. Dictionary of Computer and Internet Terms. 10th ed. New York, 2009. Print.