PDF BasicsFoundation
What Is a PDF?
A PDF is a document format designed to keep pages looking consistent across devices, apps and operating systems.
4 min readRead guide
Start here
PDF Basics
Understand how PDF files work, what they preserve and when a PDF task needs conversion, compression or OCR.
PDFs are designed to keep documents consistent across devices, but that also means some tasks require the right workflow. This hub explains the core terms before you choose a tool.
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Guides for pdf basics
PDF BasicsFoundation
What Is PDF Compression?
PDF compression reduces file size by optimizing how document data is stored. The result depends on what the PDF contains.
5 min readRead guide
TroubleshootingFoundation
Why Is My PDF Too Large?
PDFs usually become large because of scans, high-resolution photos, embedded fonts, attachments or unnecessary pages.
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PDF BasicsFoundation
How to Compress a PDF Without Losing Quality
The safest compression workflow is to remove unnecessary pages first, compress once, then check readability instead of repeatedly shrinking the same file.
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PDF BasicsFoundation
Compress PDF for Email
Email-friendly PDFs should be small enough to attach, readable enough to review and not password-protected unless the recipient expects it.
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PDF BasicsFoundation
How to Make a PDF Smaller for Upload
Upload portals usually reject PDFs because of size, password protection, missing pages or unreadable scans. Fix the structure first, then compress.
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PDF BasicsFoundation
PDF File Size Limits Explained
PDF size limits are set by email providers, forms and portals. The best fix depends on whether the PDF is too large because of pages, scans or images.
6 min readRead guide
ComparisonsFoundation
PDF Compression vs Optimization
Compression reduces stored data. Optimization can also clean structure, remove waste and prepare the file for a specific use.
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PDF BasicsFoundation
Scanned PDF vs Searchable PDF
A scanned PDF is usually made of page images. A searchable PDF contains selectable text that can be copied or extracted.
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PDF BasicsFoundation
How to Tell If a PDF Is Scanned
A scanned PDF usually behaves like a picture of a page. A searchable PDF lets you select and copy words.
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PDF SecurityFoundation
What Is Browser-Based PDF Processing?
Browser-based PDF processing means the browser performs the PDF task on your device instead of sending the file to a backend upload queue.
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PDF BasicsFoundation
How to Prepare a PDF for Online Submission
A submission-ready PDF should have the right pages, readable quality, acceptable file size and no password unless the portal asks for one.
7 min readRead guide
How to choose
Choose the smallest workflow that solves the task
- Learn when a PDF is better than an image or Word document.
- Understand why scanned PDFs behave differently from searchable PDFs.
- Choose the right first tool without changing the file unnecessarily.
Common mistakes
Avoid these traps
- Assuming every PDF contains selectable text.
- Using image conversion when page extraction would preserve quality better.
- Compressing repeatedly instead of checking what makes the file large.
FAQ
Questions about pdf basics
Is PDF a document format or an image format?
PDF is a document format. A PDF can contain text, vector graphics, images, forms and metadata.
Where should I start if I am new to PDFs?
Start with What is a PDF?, then use the glossary when a tool mentions compression, encryption, OCR or page ranges.