The are two main kind of actors in this project:
Knowledge implementers: They are researchers, programmers and enthusiasts that define and abstract knowledge. Programmers implement these knowledge in form of code. They provide these code in units called "expression packages". For example, there could be packages for arithmetic, equation solving, programming, plotting curves, etc.
Final users. They use the developed packages. They are researchers, students or even programmers.
Unlike common open source projects, where the collaborators belong to a closed team, in this project you do not have to be part of a central team, you do not even have to be a registered user in order to develop expression packages.
Expression packages are written by different persons, at different times, but when they are joined, they are able to cooperatively work with each other.
They can be used in several ways. The following are a few examples: