Net Document Annotation API. View, tag, comment & annotate PDF Word DOCX, Excel XLSX, PPTX, EML EMLX, VSS VSD, OTP, CAD & image file formats....HTML, Microsoft Office Word, Excel spreadsheets, PowerPoint presentations...DOCX , DOCM , DOT , DOTX , RTF Excel : XLS , XLSX , XLSB , XLSM PowerPoint...