1. ► ksh, zsh and bash all extend sh.

2. ► /etc/password stores user password in plain text.

3. ► Login shells can only be started by the system at login time.

4. ► ls --color is not a POSIX compliant option.

5. ► An user cannot change his/her finger information.

6. ► csh is an extended version of tcsh.

7. ► PATH variable is common across shells.

8. ► set and export do identical functions.

9. ► libtermcap makes use of /etc/termcap.

10. ► You cannot use a shell not listed in /etc/shells.