Part of macOS
hiddKeyboard and trackpad
○ Leave it
Handles input from keyboards, mice and trackpads.
What it is
Passes every keypress and click to macOS.
If you stop it
Input stops for a moment while macOS restarts it. Leave it.
The verdict
○ Leave it. Part of macOS, or something that starts again by itself. You never need to close these.
In Activity Monitor
hidd
From Procession’s guide, in the words the app shows.