By: Robert Soares | A PDF (Portable Document Format) is a file that looks the same no matter where you open it. Your computer, your phone, your client's ancient laptop. The fonts stay put. The images don't shift. What you see is what they see.
That's the whole point. And it's why PDFs became the standard for anything important.
Why PDFs Took Over
Adobe created the PDF in 1993 through something called "The Camelot Project." The goal was simple: let people share documents without worrying about whether the other person had the right software or the right printer.
It worked. By 2008, the format was so widely adopted that the International Organization for Standardization turned it into an open standard (ISO 32000). Anyone could build tools that read and write PDFs. (For the full story of how PDF evolved from a 1991 internal paper to global standard, see our history of PDF.)
Today, over 2.5 trillion PDFs exist worldwide, with roughly 290 billion new ones created each year. That's not a typo. Trillion with a T.
What Makes PDFs So Useful?
They work everywhere. Windows, Mac, Android, iPhone. Browser, desktop app, email attachment. A PDF opens the same way in all of them.
They preserve formatting. Send a Word doc and it might look different on someone else's computer. Send a PDF and it won't. The layout is locked in.
They're secure enough. You can password-protect them, encrypt them, add digital signatures. Not bulletproof, but good enough for contracts, tax forms, and medical records.
They're small. A well-compressed PDF takes up less space than the original Word or PowerPoint file. Easier to email. Easier to store.
Where You'll See PDFs
Pretty much everywhere that matters.
Business documents. Contracts, invoices, proposals, reports. When something needs to look official and stay that way, it's a PDF.
Government forms. Over 90% of government forms are now distributed as PDFs. Tax returns, permit applications, court filings.
Education. Syllabi, assignments, textbooks, lecture notes. Students and teachers trade PDFs constantly.
Publishing. Ebooks, magazines, catalogs, brochures. Anything that needs consistent layout across devices.
Working with PDFs
You'll eventually need to do more than just read them.
Merge PDFs. Combine multiple files into one. Our free merge tool handles this without uploading your files anywhere.
Compress PDFs. Shrink oversized files so they'll actually send via email. Try our compress tool.
Split PDFs. Extract specific pages from a larger document. Useful when you only need part of a contract or report.
Edit PDFs. Trickier than it sounds. PDFs aren't designed for editing. Adobe Acrobat does it well. Free alternatives exist but have limits.
For a deeper look at what's possible, check out our PDF tools guide.
The Limits of PDFs
PDFs are great at being static. That's also their weakness.
You can't tell if anyone read it. Send a proposal as a PDF attachment and you're just guessing whether they opened it. Did they get to the pricing section? No idea.
They sit in download folders, forgotten. Email attachments are easy to ignore. Most get opened once, if at all.
They're passive. No interaction, no engagement metrics, no way to update the content after you've sent it.
Mobile experience varies. While 63% of PDF views happen on phones and tablets, the experience isn't always great. Pinch-to-zoom on a document designed for 8.5x11 paper gets old fast.
When a Flipbook Beats a PDF
This is where interactive flipbooks come in. A flipbook takes your PDF and turns it into something that works better online.
Instead of a static file attachment, you get a shareable link. Instead of guessing whether someone read it, you get analytics. Page views, time spent, which sections got attention. Instead of a document optimized for printing, you get one optimized for screens.
Sales proposals, product catalogs, training materials, annual reports. Anything where you need to know if people actually read it. That's where flipbooks shine.
Our flipbook guide covers this in detail. The short version: PDFs are for documents that need to be downloaded, printed, or archived. Flipbooks are for documents that need to be read, shared, and tracked.
Quick Reference: PDF Basics
File extension: .pdf
Created by: Adobe (1992)
Standard: ISO 32000-2:2020 (PDF 2.0)
Opens with: Adobe Acrobat Reader (free), Preview (Mac), most web browsers, countless other apps
Best for: Contracts, forms, archival documents, print-ready files
Not great for: Interactive content, tracking engagement, mobile-first reading
Next Steps
Need to work with PDFs right now? Our free PDF tools let you merge, compress, and split without uploading to third-party servers.
Ready to make your PDFs more engaging? See how Flipbooker turns static documents into interactive flipbooks with built-in analytics.