What does DPI really mean?

Hi everyone,
Why in Unreal Engine we use the term DPI (dots per inch) and DPI Scaling, instead of PPI (pixels per inch) which is the one for screens?

As far as I’m concerned, DPI is used for printing, and PPI for screen display.

(Other solution that could be posible is that DPI refers to the mouse sensity…)

Thank you so much for your help.
Have a nice day,
Sandra