Those “van” and “de” prefixes
Dutch surnames famously carry little words: van (“of/from”), van der/van den (“of the”) and de (“the”). They point to a place or a feature — Van Dijk “of the dyke,” Van den Berg “of the hill” — or describe a person, De Jong “the young one,” De Groot “the tall one.”
Trades and fathers
Others are occupational (Bakker “baker,” Visser “fisherman,” Mulder “miller”) or patronymic (Jansen, “son of Jan”). Many Dutch families only adopted fixed surnames in the early 1800s.