A PDF viewer that can’t and won’t change the documents it reads, opens multiple windows on the same document, and shows you the PDF source code. Important update for Big Sur and later, including Tahoe.
Quartz
At the heart of the first Macs, its support for Regions was unique, and it could replay drawing instructions in a Picture, the basis of its PICT file format. Then came Mac OS X with Quartz.
PDF was introduced by Adobe in 1993, when its viewer Acrobat became popular, and PDFs were created from PostScript using Distiller. Then came Preview from NeXT to Mac OS X.
How should you keep copies of web pages: HTML source, Webarchive, or PDF? Which is the better way to make PDFs in Safari? And what about archive copies?
Metal provides low-level access to 3D graphics, rendering and compute features in GPUs. With the deprecation of OpenGL and OpenCL, it’s vital, especially for M1 Macs/
Six different PDF documents, all scrolling in unison when one pages through its thumbnails. Not a special effect – a bug in macOS Mojave.
A close look at just what macOS PDF support and Preview can do well, including a hidden file conversion feature.
The Eclectic Light Company 