Almost everything we do is time dependent. Every mutation splits the temporal state of the program in two: one before the change, and one after. For a simple system, we can precisely define any state based on the initial state and the lines of code. It evolves in a deterministic, predictable way.
But many programs aren’t that simple. In a concurrent system, there is no single timeline. We have multiple actions that can happen in any order, producing a fractured spread of new time lines. Concurrent systems describe everything from threads sharing memory to independent actors to changes in our real world. ...
