What is a PDF?
A PDF is a Portable Document Format file: a document designed to keep its layout consistent when it is opened, shared, or printed on different devices.
What does PDF mean?
PDF stands for Portable Document Format. It was made for documents that should look substantially the same wherever they are viewed. A résumé, invoice, manual, school form, or print-ready design can keep its page size, type, spacing, images, and page breaks instead of changing to match another computer's fonts or software.
A PDF is a file format, not an app. You can open PDFs in a browser, a PDF reader, or many operating systems without needing the program that created the original document.
Why are PDFs used?
People use PDFs when presentation matters. A shared Word document can reflow when a recipient lacks a font or uses a different version of the software. A PDF is usually the better handoff format when the reader should see a fixed page layout.
- Sharing: send a document that is easy to open and review.
- Printing: preserve page dimensions, margins, and page order.
- Records: keep a stable copy of a statement, receipt, contract, or completed form.
- Publishing: distribute a brochure, report, menu, portfolio, or guide.
What can a PDF contain?
A PDF may contain selectable text, vector shapes, photographs, scanned pages, fonts, links, form fields, annotations, and multiple pages. This is why two PDF files can behave very differently: one may be a small text document, while another is a large scanned book made from hundreds of images.
Some PDFs contain real text that can be searched and copied. A scan may only contain a picture of text. Optical character recognition (OCR) can add a searchable text layer to a scan, but converting a PDF page to an image does not create that text layer.
PDF vs. Word, JPG, and PNG
PDF vs. Word
Use Word or another editable document format while writing and revising. Use PDF when you want a stable version for reading, sharing, or printing.
PDF vs. JPG
A JPG is one raster image. A PDF can hold many pages, text, vectors, and links. Convert a PDF to JPG when a page needs to be used as an image in a slide, post, or upload.
PDF vs. PNG
PNG is also an image file and is often useful for sharp text, diagrams, and transparent graphics. It does not preserve selectable PDF text or multi-page document structure.
How do you work with a PDF?
The right action depends on the goal. To share a page as a picture, convert PDF pages to JPG, PNG, or WebP. To combine documents, use the PDF merger. To pull out only the pages you need, use Split PDF. To make a PDF from photos or screenshots, use the JPG to PDF or PNG to PDF converter.
If a document is sensitive, check where processing happens before uploading it. pdftoimg processes these tools in the browser, so the selected file stays on your device while you work.
Common questions
Is a PDF an image?
Not necessarily. A PDF can contain images, but it can also contain text, vectors, links, forms, and several pages. A scanned PDF may be made mostly from images.
Can a PDF be edited?
Some PDFs can be edited when you have the right software and permissions. A PDF is often shared precisely because its layout is intended to be stable, so editing is usually less direct than editing the original document.
Why is my PDF file so large?
Large scanned pages, high-resolution photos, embedded fonts, and many pages all increase file size. The number of pages alone does not determine it.
Is PDF the same as Adobe PDF?
PDF is the file format. Adobe created the format and makes software for working with it, but PDFs can be created and read with many different tools.