DF files are a common file type that is often used to share documents. They contain text and images, so they can be large. If you have an important PDF document that you need service with someone but would like it to be smaller, there are ways to compress the file size. One way is by converting the PDF into a word document or PowerPoint presentation, then removing any unnecessary text or graphics from those presentations before sending them out via email or uploading them on social media sites like Facebook or Twitter.