How does one erase all of "more information" in a file created my any mac?

[ET iPhone Home]

When looking into "get info" within a file, each file, whether it be jpeg, word doc, pps has information from the creator, how does one erase this?

I, along with a group at work, work together on projects. I'd like to share the credit by not having my information on the file, if I'm the last person to edit it.

Thanks.