The commonly used file format for exchanging documents is PDF (Portable Document Format). PDF files maintain their original formatting across different devices and platforms, making them ideal for sharing documents that require consistent presentation. PDFs can encapsulate text, images, fonts, and other elements in a single file, allowing for rich document design. Additionally, PDFs support features like annotations, forms, and digital signatures, enhancing interactivity without altering the document's integrity. This makes PDFs a preferred choice for business communications, legal documents, and academic papers.