Open source is a model of development where plans are available to other people.
First created for software (where it became successful with Linux) it is gradually expanding. To text (e.g. Wikipedia), but also some hardware and even soft drinks.
It is being used to some extent among custom manufacturing enthusiasts.
It will be used in the future in biotech and nanotech development, where exact descriptions of products/technologies are available by default, because everything is done in simulations and then automatically synthesized.