This method will generate a PDF file whose quality is closer to the original PowerPoint slides than any other software does (e.g., Adobe Acrobat, etc.). Generally it can prevent the fonts from being distorted and ameliorate losses of image quality during the conversion to the PDF file. However, it has one drawback. If one uses the Adobe Acrobat Reader in Linux to read the PDF file generated by this method, one would find the font looks different from the original file. This problem only occurs if one uses the Linux version of Acrobat Reader. If one uses other PDF readers in Linux to display it, there won't be any problem. Except for the Acrobat Reader in Linux, Acrobat Reader in Windows or Mac OS can both display this PDF file normally.