“Reactive Programming” is such a wide umbrella of concepts and architectures that two different resources explaining Reactive Programming might seem to contradict each other at times while agreeing with each other otherwise. There’s a lot more to the fundamental idea of Reactivity than what you might get from a single blog post. This talk will attempt to take a higher-level look at Reactivity, describe the anatomy of a Reactive system, and how differences in specific characteristics like push vs pull, sync vs async, and eager vs lazy result in very different architectures and trade-offs. We will also see how these systems are similar or dissimilar to each other using a visual interactive map.