Shell scripting concepts covered in this lesson:

• Getting input from the person executing the script using the read shell builtin.

• Introduction to standard input, standard output, and standard error.

• Creating accounts with the useradd command.

• Username conventions including length, case, and valid characters.

• Using the “-” or “-l” options to the su command to simulate a full login when switching users.

• Controlling the default account creation behaviors by editing the /etc/login.defs file.

• Using quotes to make a string that contains spaces behave as a single argument or item.

• Setting passwords with the passwd command interactively and programmatically.

• Using pipes to chain together multiple commands.

• Expiring accounts with the passwd command