Plain-English guide to the Portable Document Format — how PDF works, why it became the global document standard, and when you should and shouldn't use it.
PDF — Portable Document Format — was invented by Adobe co-founder John Warnock in 1991 to solve a single problem: how do you send a document to someone and trust that it will look exactly the same on their machine as it did on yours?
The first version shipped in 1993. By 2008 the format was open and standardised as ISO 32000-1, and today there are an estimated 2.5 trillion PDFs in existence — more than every Word document, spreadsheet and slide deck combined.
A PDF is a self-contained package: text, fonts, vector graphics, raster images and form data, all glued together with a tiny rendering language derived from PostScript.
Because fonts are embedded, a PDF opened on a Windows laptop, an iPhone and a 1995 Solaris workstation will render with the same line breaks, the same kerning and the same colour profile.
Use PDF when fidelity matters more than editability: contracts, invoices, academic papers, government forms, archival records, anything you'd print.
Avoid PDF when collaboration matters more than fidelity. Use Google Docs or Word for living documents and only export to PDF at the end.
Yes, with the right tool. PDFWix's Edit PDF tool lets you change text, add images, redact, sign and reorder pages directly in the browser.
Because fonts and layout are embedded in the file itself, not loaded from the operating system.