What is a shell in Linux?

Answer 1

Typically.... Bash. Could also be tcsh, zsh, or pdksh. Or something really weird. Try:

echo $SHELL and see what that gets you. Shell is a software program that allows you to interact and access a computer system. User can enter commands in the shell prompt, which will be executed by the shell. Since the only means of communication through shell is text, it is known as Command-Line-Interfaceor CLI.
A shell is a command interpreter and serves as a user interface to the Linux kernel

Answer 2

Unix has two main sets internal implementation and the interface that is seen and used by users. i.e. Kernal and Shell.

Kernal takes care of hardware interface and shell communicates with Kernal.

Shell works as interpreter of user commands and translates them into action. The shell forms the outer part of the operating system and forms the interface between the user and the kernel.

For each user logged in, there is shell in action. When a command is given by the user, it is examined by the shell and communicated to the kernel for execution.

The functions used to communicate with the kernel are called system calls and are built into the kernel. The system calls are in all the flavors of UNIX are the same. Hence, software developed on one UNIX system can be easily run on another UNIX system.

shell also has some internal commands, e.g. CD. External commands are saved in file system, when you enter such commands shell searches for them and runs them in new sub-process.

application developed on unix communicates with shell and not kernal, this engables single application to be executed on various types of computer hardware without being modified

Answer 3

its the outer layer of OS which acts as interface between dthe application or utilities and the kernel(OS core - codes)