PS in original novels usually referred to Post-Script or PDF.It was a kind of file format used to output high-quality graphics, images, text, and other content on a computer. The PDF-format can contain many types of content, including text, images, tables, pictures, and so on. It can also be optimized by different typography and printing methods to improve its legibility and aesthetics. Normally, the PDF-format was used in novels, magazines, newspapers, flyers, posters, and other media to improve the quality and legibility of the content.