The influence of Armando 'Chick' Corea pervades most of contemporary jazz.  His compositions, performances and recordings stand as powerful milestones in the development jazz (in particular) and music (in general) during his lifetime.  Anyone that needs a primer in Chick Corea could start with Wikipedia and follow the links (you may need to pack a lunch...).  And the rest of us may never assimilate all of his work, but it's worth a try!