Introduction
Create accessible PDFs with proper tagging for screen readers and WCAG compliance. This is an advanced guide for experienced users and developers. We'll dive deep into the technical details, edge cases, and professional workflows. Whether you're using PDFly's free online tools or building your own workflow, this guide covers everything you need to know about pdf tags and accessibility pdfua.
Understanding Basics
The PDF (Portable Document Format) was created by Adobe in 1993 and has become the global standard for document exchange. Understanding how PDFs work at a fundamental level helps you make better decisions about document creation, editing, and sharing. PDFs preserve formatting across devices, platforms, and operating systems, making them ideal for everything from legal contracts to simple memos.
Key Concepts You Need to Know
- PDF stands for Portable Document Format — designed to preserve formatting across all devices
- PDFs can contain text, images, vector graphics, interactive elements, and embedded fonts
- The PDF specification (ISO 32000) is an open standard maintained by ISO
- PDFs support layers, bookmarks, hyperlinks, annotations, and form fields
- Different PDF versions (1.0 through 2.0) offer varying features and compatibility
Tips & Best Practices
Start with simple operations (merge, split) before tackling advanced tasks
Always keep original files as backup when learning new operations
Use browser-based tools like PDFly — no installation needed and 100% private
Learn keyboard shortcuts in your PDF viewer for faster navigation
Understand file size implications when creating PDFs
Common Mistakes to Avoid
- Confusing PDF with other document formats like Word or HTML
- Not understanding that PDFs can contain interactive elements
- Assuming all PDF viewers display documents identically
- Ignoring PDF version compatibility when sharing documents
- Not realizing that PDFs can embed fonts, images, and multimedia
Code Example
// Example: Using PDFly's client-side API
const file = document.getElementById('file-input').files[0];
const arrayBuffer = await file.arrayBuffer();
// Process PDF entirely in the browser
const result = await pdfly.process(arrayBuffer, {
operation: 'compress',
level: 'medium'
});
// Download the result
const blob = new Blob([result], { type: 'application/pdf' });
const url = URL.createObjectURL(blob);
window.open(url);