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Some PDF files are text, images, and graphics that are so indexed within the file that they can be extensively edited in Adobe Acrobat.  Others are crude scans that consist of a single image - like a photocopy or photograph - of something that happens to be saved within a PDF file.  With the latter, Adobe's tools may be able to do little or no editing, besides perhaps crude text overlay or annotations.  What Acrobat can do with a scanned document depends on the quality and condition of the paper original, and the circumstances of it's scanning.  

PDF files can be a combination of other files, that have either been amalgamated into a single PDF file, or simply stored and displayed together within a single PDF container.  For simplicity's sake, this guide shows you how to create the former, and that's what is meant here by "portfolio." 

Adobe Acrobat's "PDF Portfolio" tool allows you to create the latter, where your .docx, .jpg,, .pptx, and other file types keep those identities and remain independently editable.  While practical for some uses, this creates a complicated file for your readers, wherein they must take special steps to view the included contents.  So for many projects, Adobe's PDF Portfolio is not the best choice. 

Creating PDF Files or Pages using Microsoft Word

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