Oh, honestly. Pokémon was first created in 1995, I know that. When was digimon made, 1996/7/8 (not sure, somebody tell me please) so pokémon came first. Digimon was just called a ripoff of Pokémon because pokémon aired first in US and because the both end in -mon. They are almost nothing alike really, except for people with monsters who wish to get stronger. In pokémon, you collect them and try to be a master and the pokémon can't talk human (except for a few exceptions, including Meowth, Mewtwo and Lapras) while in digimon they team up with one digimon (or in Willis' case 2) and together you keep peace in each others worlds. They are really nothing alike.
Rant over.