What makes ink colored?

Answer 1

Let me preface this briefly with a little modern printing history.

In the early days of color printing, with the devolpment of the three color process (cyan, magenta, and yellow) there were two ways to print black. Printers could pass board (paper) through the press in a first pass and print all black areas;typically this was for jobs with large black areas. Or, board would print in one pass, and a mixture of the three colors would produce a shade of black.

Essentially, cyan, magenta, and yellow (CMYK) will make black.

Because CMYK does not produce a perfect black, four color presses were developed that included black ink application.