Class Libraries & REST APIs for the developers to manipulate & process Files from Word, Excel, PowerPoint, Visio, PDF, CAD & several other categories in Web, Desktop or Mobile apps. Develop & deploy on Windows, Linux, MacOS & Android platforms....sample value to "A1" cell worksheet . Cells [ "A1" ]. PutValue...sample value to "A2" cell worksheet . Cells [ "A2" ]. PutValue...