What is .pdf?
.pdf (Portable Document Format) is a versatile file format created by Adobe that presents documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems.
This quick guide explains when to use .pdf files, how to open them on any device, and how to share them instantly with FileXhost.
When to use .pdf files
- You need to share a document that looks exactly the same on every device.
- You are sending forms, contracts, or legal documents.
- You want to prevent accidental layout changes (unlike Word documents).
- You need to combine text, images, and vector graphics in a single file.
How to open .pdf files
PDF files open natively in all modern web browsers (Chrome, Edge, Safari, Firefox). You can also upload .pdf files to FileXhost to view them directly in a clean, distraction-free browser viewer or share them as a professional link.
Algorithm details
PDF encapsulates a complete description of a fixed-layout flat document, including the text, fonts, vector graphics, raster images and other information needed to display it. It can contain interactive elements like annotations, form fields, layers, rich media, and 3D objects using U3D or PRC. Compression techniques include LZW, Flate (Deflate), JPEG, and JPEG 2000.
Browser & platform support
- Desktop: Native support in Chrome, Firefox, Safari, Edge, and Opera.
- Mobile: Native support in iOS (Safari/Files) and Android (Chrome/Drive Viewer).
- OS: Native support on macOS (Preview), Windows 10/11 (Edge), and most Linux distros.
Format comparison
| Feature | Details |
|---|---|
| Consistency | Preserves layout, fonts, and images exactly as intended, unlike DOCX or HTML. |
| Security | Supports encryption, password protection, and digital signatures. |
| Interactivity | Can contain forms, links, buttons, and even JavaScript. |
| Editability | Designed for viewing, not editing. Harder to modify than Word documents. |
How to create pdf files
- Word Processors: Microsoft Word, Google Docs, Pages (Export as PDF).
- Design Software: Adobe InDesign, Illustrator, Canva.
- Browsers: Print to PDF from any webpage.
- Scanners: Default format for multi-page scanned documents.
How to convert pdf files
- FileXhost: Upload PDFs to view, share, or embed.
- Online tools: Smallpdf, iLovePDF, Adobe Acrobat Online.
- Desktop: Microsoft Word (opens PDF to edit), Adobe Acrobat.
- CLI: Pandoc, Ghostscript.
Advantages & disadvantages
Advantages
- Universal compatibility across all devices
- Preserves formatting exactly
- Supports security features (passwords, signatures)
- Compact file size for text-heavy documents
- Industry standard for printing and sharing
Disadvantages
- Difficult to edit without specialized software
- Can be difficult to read on small mobile screens (if not reflowable)
- Complex PDFs can be large and slow to render
Tools & software
Viewers
Adobe Acrobat Reader, Web Browsers, Foxit Reader, macOS Preview
Editors
Adobe Acrobat Pro, Nitro PDF, PDFelement, LibreOffice Draw
Converters
FileXhost, Smallpdf, CloudConvert, Microsoft Word
Libraries
PDF.js (Mozilla), PyPDF2 (Python), iText (Java/C#), pdf-lib (JS)
Frequently asked questions
How do I edit a PDF file?
PDFs are designed for viewing, not editing. To edit text, you need specialized software like Adobe Acrobat Pro, or you can convert it to Word (DOCX), edit it there, and save it back as PDF.
Why can't I copy text from my PDF?
The PDF might be a scanned image (raster) rather than actual text, or the author may have applied security settings to prevent copying. OCR (Optical Character Recognition) tools can help convert scanned PDFs to searchable text.
Is PDF better than Word?
For sharing final documents, yes, because PDF ensures the layout stays the same. For drafting and collaborating on documents, Word is better because it's easier to edit.
Are PDF files safe?
Generally yes, but like any file, they can contain malicious scripts. Always be cautious when opening PDFs from unknown sources. FileXhost scans files for basic integrity.
Technical specs
- File type
- Document
- Extension
- MIME type
- application/pdf
- Compression
- Lossless
- Max file size on FileXhost
- Up to 25 MB per file on the free plan and up to 1 GB on Pro FileXhost accounts.
Share .pdf files instantly
Upload your .pdf file to FileXhost to get a clean, shareable URL in seconds. View the file in a modern browser, protect access with optional settings, and let others download it without any confusing ads or cluttered file pages.
Upload .pdf file