In Windows file properties, it's called 'Program Name' under Origin. In Adobe Bridge, it's called 'Application' under File Properties.
I believe it adds the name of the program used to create the file. It cannot be edited/removed in Bridge or Windows.
I really don't understand how it gets added because certain images taken from a camera and edited in Lightroom does not add the attribute, and other times it does. One file was edited in Photoshop and tagged Photoshop, but …