Glossary

Glossary pages define one term each — what it means, why it matters for your documents, and where it shows up in PDFLean tools. Terms live in their own section so guides can link to a definition once instead of re-explaining it every time. Every entry carries a concrete example, and every entry names the PDFLean tools that actually work with the concept.

Glossary

Plain-language definitions of PDF, privacy, and compliance terms used across the docs.

• Bates Numbering — A sequential identifier stamped on every page of a document set so any page can be cited precisely
• Bookmarks (Outline) — The document's table of contents, stored separately from the pages and shown in the reader's sidebar
• Cross-Reference Table — The index that tells a PDF reader where every object in the file sits, and what breaks when it is damaged
• Factur-X and ZUGFeRD — The standard for embedding a machine-readable invoice inside a PDF/A-3 file, so one document serves people and software
• Flattening — Converting form field values into permanent page content so they display in every viewer
• Font Embedding and Subsetting — Including a document's fonts inside the file so it renders identically everywhere, and subsetting to embed only the glyphs used
• Form Field — An interactive region on a PDF page that holds a value, identified by a name the file carries
• Grayscale — Converting a document's color to shades of gray, for ink cost and often for smaller files
• Imposition and N-Up — Arranging a document's pages onto printed sheets — multiple pages per sheet, folded booklets, or tiled posters
• Incremental Update — The way PDF editors append changes at the end of a file instead of rewriting it, and a hidden source of size growth
• Linearized PDF (Fast Web View) — A PDF reorganized so the first page renders before the rest of the file finishes downloading
• Lossless and Lossy Compression — The one distinction the whole compression family turns on — identical output, or smaller at a visible cost
• Object Streams — Compressed containers inside a PDF that hold many small objects, and the main lever of lossless size reduction
• OCR Text Layer — Invisible text placed over a page image so a scan can be searched, selected, and read by machines
• PAdES — The PDF standards family for digital signatures applied and verified with certificates
• Page Content Stream — The sequence of drawing operators that describes everything a page looks like
• PDF Encryption and Permissions — A user password that opens a file and an owner password that controls what may be done with it — and why neither removes content
• PDF Metadata — Information about the document stored separately from the page content, and a common place for leaks
• PDF/A — The ISO 19005 subset of PDF built for long-term archiving, where everything needed to render the file is inside it
• PDF/UA (Accessible PDF) — The ISO 14289 standard for PDFs that screen readers and other assistive technology can actually read
• PII (Personally Identifiable Information) — Data in a document that identifies a specific person, and the usual target of a redaction pass
• Preflight — Checking a print-ready PDF against production requirements before it goes to press
• Raster and Vector — The two ways a page's appearance can be carried — a grid of pixels, or drawing instructions that scale
• Redaction — Removing content from a PDF so it is gone from the file, rather than covered up by a box
• Watermark — Text or an image placed across every page to carry status or origin, from DRAFT to a company logo
• ZIP Archive — A compressed container holding many files, and the usual way multiple PDF outputs are delivered together

How the entries are organized

Each glossary page has the same three parts: a definition in plain language, a worked example that shows the term in a real document situation, and the tools in PDFLean that operate on it. Read an entry when a guide points at it, or browse the list above when a term shows up in a tool page and you want the background.

Related reading

• Object Streams — the term behind most lossless compression work
• Form Field — the term behind every fill-and-sign job
• Tool Guides — where most terms are put to work