Portable Document Fomat (.pdf)
PDF stands for Portable Document Format. It is a versatile file format created by Adobe in 1992 to present and exchange documents independent of software, hardware, and operating systems. It is now an open standard maintained by the International Organization for Standardization (ISO). PDFs can contain links, buttons, form fields, audio, video, and business logic and can be signed electronically. They can easily be viewed using the free Adobe Acrobat Reader software.