They were linguists, and studied comparative languages. Grimm"s law named in their honor.

Benno Grimm has written:

'Die Ehelehre des Magister Honorius' -- subject(s): Marriage (Canon law)

Paul W. Grimm has written:

'Managing e-discovery and ESI' -- subject(s): Electronic discovery (Law)

The brothers were linguists and linguistic scholars. ( they worked on editing dictionaries and such like) there is a Grimm"s law in languages. (applies only to European tongues). Folk and fairy tales were a profitable sideline or hobby.

The Grimm brothers, Jacob and Wilhelm, contributed to philology by compiling the first comprehensive German dictionary, known as the Grimm's Dictionary. They also collected and published folklore and fairy tales, helping to preserve and document the German language and cultural heritage. Additionally, their work on Grimm's Law in historical linguistics has been influential in the study of language evolution.