su:tldr:0b180

The "su" command is short for "switch user" and is most commonly used in Unix-like operating systems, including Linux. The command allows you to change the current user without logging out or rebooting the system.

By default, if you simply type "su" in the terminal without any additional parameters, it will prompt you to enter the password of the superuser or root account. Once authenticated, you will switch to the root user, providing you with full administrative privileges.

However, you can also specify a different user to switch to by typing "su" followed by the username, such as "su johndoe". In this case, you will need to enter the password for that specific user account.

Using the "su" command is particularly useful when you need to perform administrative tasks that require elevated privileges or access files and directories restricted to a specific user.