This was created for the Mac OS X operating system. Unlike the old operating environment versions, the font is stored in the thread of a data file instead of in resource threads. It’s been used as a container for TrueType fonts since 2009 after the release of Mac OS X 10.6, and is gradually replacing the TrueType Collection.
This format was developed by Apple for storing vector and bitmap images with metadata. It was the main format for the QuickDraw graphics software. PCT supports 32-bit and 24-bit images. At the moment, the format is obsolete and has been superseded by more functional solutions.