A company changes its colours about once a decade, and when it does, every drawing in every document has to be repainted. If those colours were written into the drawings themselves, that means a hunt through a great many files — and the one that gets missed is the one that goes to print.
Here the colours live in one chart the file carries, and the drawing carries only places in that chart — sixteen of them. The same drawing is shown a second time on the page, against a second chart, and it comes out in entirely different colours without one mark of it being touched. That is a whole brand repainted by changing one chart, instead of hunting through every drawing that ever used the old colours.
Nothing is left out and nothing is simplified: this is the program exactly as it runs, for the developer who uses this library. The third is the description itself: a plain list of what the page has to say, which is what the service is sent.
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The document is lighter than it was, and every page still looks exactly the same. See this document's row in the table of every example.
Swatches in each of the three ways to say a colour — a grey as one number, a screen colour as three, a printing colour as four inks — each captioned with the instruction actually written into the file, and one mid-grey said three ways.
The same six colours said as bare numbers and then read through the screen profile the file carries, plus a ramp from light to dark and a sweep of measured hues: colour that still means the same thing on another screen and on a press.
Two inks the press carries on a plate of their own, each at ten strengths, a piece of work set in both, and the alignment crosses used to line the plates up — drawn in an ink every plate answers to.
Eight choices of plate among the four usual inks, each with the small program that shows it printed underneath, and two inks the press carries itself used together, every strength of one against every strength of the other.
One pattern that states no colour of its own, laid down in five colours and in five strengths of one press ink: the fill says what colour to lay it down in. Beside them, the same hatch made of patterns that carry their own colours, which is one pattern per colour.
One drawing on three pages: a press sheet stating where the ink runs, where the blade falls and what is worth keeping, with trim marks; the same sheet cropped to the finished page; and a landscape page that states a quarter turn clockwise on an upright sheet.