PDF Glossary
Master the technical world of PDF management. We explain the most common terms in simple language to help you manage your documents like a pro.
AES-128 / AES-256
Advanced Encryption Standard. These are world-standard algorithms used to secure digital documents. PDF Toolkit utilizes 128-bit AES to protect your PDF files with high-strength passwords efficiently in your browser.
ArrayBuffer
A generic, fixed-length raw binary data buffer. In our toolkit, this is how your PDF is handled internally before being processed by WebAssembly.
Asynchronous Processing
A method of running computer tasks in the background without freezing the user interface. This ensures that while a PDF is merging, you can still interact with the page.
Blob (Binary Large Object)
A way to represent raw data that doesn't necessarily follow a traditional file format. When you "Merge" or "Split", we convert the result into a Blob so your browser can download it as a PDF.
Browser-Side Processing
A modern technique where all calculations happen on the user's device instead of a remote server. This is the foundation of PDF Toolkit's privacy — your files never leave your computer.
DPI (Dots Per Inch)
A measure of spatial printing, video or image scanner dot density. High DPI (like 300) results in crisp, clear images from your PDF pages.
Encryption
The process of encoding information so that only authorized parties (those with the password) can access it. Our toolkit applies this directly on your device.
JSON-LD
Javascript Object Notation for Linked Data. We use this "hidden" code on our pages to help search engines like Google understand our tools better, improving your search results.
Lossless Compression
A data compression algorithm that allows the original data to be perfectly reconstructed from the compressed data. Ideal for text-based PDFs.
Metadata
Data that provides information about other data. In a PDF, this includes the title, author, creation date, and keywords that aren't visible in the document text.
OCR (Optical Character Recognition)
The mechanical or electronic conversion of images of typed, handwritten or printed text into machine-encoded text.
PDF (Portable Document Format)
A file format developed by Adobe to present documents in a manner independent of application software, hardware, and operating systems.
PDF/A
An ISO-standardized version of the PDF specialized for use in the archiving of long-term digital documents.
pdf-lib
A powerful open-source library that PDF Toolkit uses to modify PDF documents directly in the browser via JavaScript.
Permissions Password
A password that restricts specific actions like printing, editing, or copying text from a PDF, even if the user can open it.
Public URL
The long-term web address where a file is stored. When you use our dashboard, your files are saved via Cloudflare R2 and given a secure Public URL for history retrieval.
R2 (Cloudflare R2)
A highly secure, global object storage service. We use R2 to store your processed PDF history safely while keeping it accessible from your dashboard.
Raster vs. Vector
Raster images (like photos) are made of pixels. Vector images (like PDF text) are made of mathematical paths. Vector PDFs stay sharp at any zoom level.
Session Management
The process of securely handling your login state. We use JWT (JSON Web Tokens) to ensure your PDF history is only visible to you.
Sitemap
A file where you provide information about the pages, videos, and other files on your site, and the relationships between them. It helps Google crawl your site efficiently.
Watermark
A faint design or text made in some paper or digital documents during manufacture or processing. Used to indicate "Confidentiality" or ownership.
WebAssembly (Wasm)
A low-level assembly-like language with a compact binary format that runs with near-native performance in web browsers. This is why our PDF tools are so fast.
Web Worker
A script that runs in the background, separate from the main execution thread of a web application. We use them so complex PDF tasks don't slow down your browser.
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