What is the chief difference between the –v and –x option s to set?
The –v option echoes each command before arguments and variables have been substituted for; the –x option echoes the commands after substitution has taken place.
6) What is Kernel?
Kernel is the UNIX operating system is the master program that controls the computer's resources, allotting them to different users and performing different tasks. However, the kernel doesn't deal directly with a user. Instead, it starts up a separate, interactive program, called a shell, for each user when he/she logs on.
7) What is Shell?
A shell acts as an interface between the user and the system. As a command interpreter, the shell takes commands and sets them up for execution.
8 ) What are the key features of the Korn Shell?
  • history mechanism with a built-in editor that simulates emacs or vi
  • built-in integer arithmetic
  • string manipulation capabilities
  • command aliasing
  • arrays
  • job control
9) What are some common shells and what are their indicators?
  • sh – Bourne shell
  • csh – C SHell
  • bash – Bourne Again Shell
  • tcsh – enhanced C Shell
  • zsh – Z SHell
  • ksh – Korn SHell