Group Demo, OpenMDAO 2.x
![](https://openmdao.org/wp-content/uploads/2018/06/24_GroupDemo.gif)
Some code and an illustration that attempt to show the relationships between Components and Groups in OpenMDAO 2.x.
Explicit Connection Demo, OpenMDAO 2.x
![](https://openmdao.org/wp-content/uploads/2018/10/24_ExplicitConnectionDemo.gif)
Some code and an illustration that attempt to show how an explicit connection happens in OpenMDAO 2.x.
Problem Demo, OpenMDAO 2.x
![](https://openmdao.org/wp-content/uploads/2018/10/24_ProblemDemo.gif)
Some code and an illustration that attempt to show how Problems, Drivers, and Solvers work together in OpenMDAO 2.x.
Promotions Demo, OpenMDAO 2.x
![](https://openmdao.org/wp-content/uploads/2018/10/24_PromotionDemo.gif)
Some code and an illustration that attempt to show promotion works in OpenMDAO 2.x.