Conventional printing inks
Inks and pigments have been used for printing on to various substrates for many years. By mixing different colours you can achieve a much wider variety of palettes, which is how and why magazine printing only uses a basis four different coloured inks to then produce the spectrum of colours which make up a finished, printed magazine.
The four colours used are yellow, cyan, magenta, yellow, and black. When the paper passes through each inking station of a printing press, a cylindrical plate which has an etched image of the text pages picks up one of the specific colours and transfers it on to the paper as the paper passes through the inking station. The paper than passes through the other three inking station which builds up the full colour images on the paper.
The printing plates put ink down on the paper in very small dots, which can be seen with a magnifying glass. If you want to achieve different colours, the density of the dots increases which to the naked eye looks like you are creating a new colour. For example, to achieve an orange colour on a specific area, one printing plate in the yellow inking station will be etched in that specific area, so it picks up the yellow ink and puts it down on the paper. Then as the paper passes through the magenta inking station, that printing plate will be etched in the same area so magenta ink will be put down on the same area, thus creating an orange image, as it contains yellow dots and magenta dots which to the naked eye make orange.
There are other ink colours of course like specials like metallic’s, but cyan, magenta, yellow, and black, known as CMYK, or the four colour process has been used for many years to print magazines in the conventional printing process.