What is PDF annotation?
PDF annotation is the process of adding comments, notes, or other information to a PDF document, making it more interactive and useful.
The latest version of the PDF standard, PDF 2.0, includes 28 types of annotations that can be used to enrich the document, including popular options such as highlighting, text notes, comments, stamps, and signature fields.
PDF annotations can also include file attachments, sound, and interactive 3D content, providing a rich set of features that allow users to work with the document in new ways. These annotations can be added using various software tools and are typically saved within the PDF file itself.
To learn more about the technical details of PDF annotation, you can refer to clause 12.5 of ISO 32000-2:2020 , the official PDF specification.
