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 is either very young or very out of touch with the art of music.  And the rest of us may never assimilate all of his work, but it's worth a try!