A PDF (Portable Document Format) file is a versatile file format developed by Adobe. It's used to present and exchange documents reliably, independent of software, hardware, or operating system. PDFs preserve the formatting of the original document, including text, images, and layout, and can be viewed on a wide range of devices.
They are commonly used for documents like forms, ebooks, and scanned documents, and support features like hyperlinks, annotations, and security options (like password protection).