423b5459__Students_at_College_of_DuPage__definition
[file extension] pdd and psd (pronounced as separate letters) [acronym meaning] ? PhotoShop Designated file [definition] 
native Adobe Photoshop graphic file formats that takes up less memory than uncompressed TIF files. Saves masks, layers, clipping paths, and alpha channels with the graphic. Not a recognized import file for all programs.
Graphic File Formats for Digital Imaging Students at College of DuPage
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