A watermark is text or an image that appears either in front of or behind existing document content, like a stamp. For example, you could apply a “Confidential” watermark to pages with sensitive information. The Watermarks can be used to protect confidential information and to indicate the validity of a legal document. You may also watermark any paper banknote, where they help to prevent counterfeiting. In this article, we are going to discuss the features related to watermark in PDF document.