What is PDF Linearization (Fast Web View)?

Linearization is a specific way of organizing the internal structure of a PDF so it can be streamed and viewed over the internet before the entire file has finished downloading.

The Standard PDF Structure

Normally, a PDF's Cross-Reference table (XRef) is located at the very end of the file. To display Page 1, a PDF reader must download the entire file to read the XRef table, find where Page 1's data is located, and then render it.

The Linearized Structure

A linearized PDF (often called "Fast Web View" in Adobe Acrobat) places a special initialization structure and a partial XRef table at the very beginning of the file. This allows browsers to immediately display the first page while the rest of the document downloads in the background.