[newbie] Chmod commands

[Zane Minninger]

Is there any way to run chmod and only affect files and not directories? I have a semi large tree and I would like any file put in it to have 664 but the directories to be 775. Any ideas or am I so new I don't know of some common and easy way. This directory can potentially have several users putting files into it. I would also like for all the chgrp to be a static group and not every persons individual group. Again, there might be something simple, I'm still pretty new.
Zane Minninger

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