system password vs administrator password in BIOS settings

I just received a new Dell laptop. In the BIOS menus, I'm able to set a "system password" but unable to set an "administrator password" (greyed out). What is the distinction between these two passwords in the BIOS.


1.System Password: This will be prompted before the system can boot up, and load the operating system.

2.Setup password: The system will prompt for this password only when you are trying to access the BIOS settings.

Source

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