PDF stands for Portable Document Format, a file format used to present and exchange documents reliably, regardless of software, hardware, or operating system. PDF files can contain text, images, links, forms, and more, making them versatile for various purposes such as sharing reports, presentations, eBooks, and forms. PDFs are widely used in business, education, and personal settings due to their consistency in formatting and ease of sharing. They can be opened with free PDF readers like Adobe Acrobat Reader, making them accessible to virtually anyone with a computer or smartphone.