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PDF Technical Glossary
Authoritative definitions of PDF technical terms, file format specifications, and stream structures.
A PDF (Portable Document Format, ISO 32000) is a file format created by Adobe in 1993 to present documents independently of application software, hardware, and operating systems. Every PDF consists of a header, body of indirect objects, cross-reference table (XRef), and trailer.
- ISO Standard 32000 specification
- Supports raster and vector drawing models
- Object stream compression architecture
- Independent of operating system fonts
A dot-matrix data structure representing a grid of pixels (e.g., JPEG, PNG) within a document canvas, as opposed to scalable vector graphics.
Geometric shapes, paths, lines, and text defined by mathematical formulas that scale infinitely without pixelation or resolution loss.
A compressed stream object introduced in PDF 1.5 containing a collection of PDF indirect objects to reduce overall file byte size.
An index table located near the end of a PDF file listing exact byte offsets for all indirect objects, enabling fast random page access.
An ISO-standardized version of PDF (ISO 19005) specialized for long-term digital preservation by disabling device-dependent features, external font links, and executable code.
A standardized color profile defined by the International Color Consortium that maps document colors across screens, printers, and scanners accurately.
The rectangular coordinate boundary box (x, y, width, height) specifying the spatial canvas dimensions of an element or character on a PDF page stream.
An external graphics object (image or form template) stored outside individual content streams and referenced repeatedly across pages.
Vector shape outlines representing specific characters stored in embedded TrueType, Type 1, or OpenType font tables within a PDF.
The process of removing hidden metadata, embedded files, underlying text streams, and deleted objects from a PDF file buffer to prevent data exposure.