PDF is a widely used document format that also supports interactive elements including Annotations, forms, 3D objects, layers, etc. Along with these elements, PDF format also supports setting restrictions such as print restriction, modification restriction, restrictions on data extraction and so on. Such features give the user more control over the document and therefore, the PDF has become a popular document format.
Since we support the rendering of PDF documents, therefore, we always keep looking to introduce features that may give you more information about the documents....interactive elements including annotations, forms, 3D objects, layers...