All file extensions
.PDF File
What is it?
PDF (Portable Document Format) preserves layout, fonts, and formatting exactly as designed, so it looks the same on any device or printer.
How do I open it?
Opens in any web browser, or in dedicated readers like Adobe Acrobat Reader, macOS Preview, or built-in OS viewers.
Is it safe?
Usually, but PDFs can embed scripts or links. Only open PDFs from sources you trust, and keep your PDF reader updated.
Can I delete it?
Safe to delete once you no longer need the document — keep a copy if it's something you may need again, like a receipt or contract.