What is emergent properties in software engineering?

Answer 1

The complex relationships between the components in a system mean that a system is more than simply the sum of its parts. It has properties that are properties of the system as a whole and cannot be attributed to any specific part of the system, known as 'emergent properties'.

There are two types of emergent properties:

1. Functional emergent properties when the purpose of a system only emerges after its components are integrated. For example, a bicycle has the functional property of being a transportation device once it has been assembled from its components.

For example, a video game developer might elect to dynamically instantiate the assets and map used for a level from an external file. That is a feature, a part of the whole. Now combine that with another feature: the ability to export level files from a map editor. Now you have two parts working together and the emergent property which arises is that the developers can make level changes without having to recompile the game.

2. Non-functional emergent properties, which relate to the behavior of the system in its operational environment. Reliability, performance, safety, and security are examples of emergent properties.

Take the above example and now give the player access to the level editor and ability to share their levels with friends. Now you have potential emergent behavior arising from that property in it's environment. Players can create levels of their own design. The developers did not design these levels, they emerged from the system.