A shell is a user interface to access an operating system using either a command-line interface or Graphical user interface. Shell Access is enabled by default on Shared hosting accounts, VPS, and Dedicated servers. There are three types of Shell Access Modes available in WHM. They are Normal Shell, Jailed Shell, and Disabled Shell.
Normal shell access grants the user to access the shell without any limitations.
cPanel and WHM use VirtFS to provide a jailed shell environment for users who connect to a server via SSH. The jailed shell acts as a container for the user and does not allow the user to access other users’ home directories on the server. Jailed shell access limits the user to use certain commands that may be harmful to the server. So that it increases the security for server’s other uses.
Disabled shell denies the user to access the shell.