hi, i'm back for a long time don't post or visit this forum...

i did the browsing all over the imdb site (don't think to buy one but only take a look for a while) and am interested at the credit titles for the 2D animation movies...especially for the animator crews, i found some vocabularies around but i don't know what its mean (though i'm an animator also). i hope some one could help me out for this...

like:
- inbetween artist and inbetween animator...what's the different? i saw those on ghibli's like Mononoke-Hime, Naushika, Howl, and Spirited Away...

and i saw these on disney's:
- key assistant (what is this? is it the same as inbetween animator?)
- assistant animator (is this also the same as key assistant? if it's true, i can't find out why they put similar work as a different thing)
- additional animator
- rough inbetween
- assistant clean-up

replies and helps please?