Signet PDF 1.x
This is the archived documentation for the 1.x line, frozen at 1.0.1. It is the prose that shipped with that release, published as it stood: the specification, the decision records and the history.
For the line that is current now, go to the current documentation.
The 1.x line had no guide. It was documented by its README, which is on the tag, and by the pages below.