OS X has a feature that allows you to take screen shots. you invoke this feature by pressing command-shift-3 (full screenshot), or command-shift-4 (select parts of the screen). this screenshot is saved as a PICT file (before OS X), PDF (OS X 10.0 to 10.3), and PNG under 10.4 "Tiger".
However, with OS X 10.4 Apple introduced an undocumented feature allowing you to change the file format from PNG (OS X 10.4 default) to other formats. savescreenie provides a graphical front end for this feature. Follow the link and
free download savescreenie now.
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