Demystifying Functors: Why They're Simpler Than You Think

This article reveals that Functors—often presented through intimidating category theory—are actually a simple, everyday pattern that every developer already uses through map(). By showing how Arrays, Promises, RxJS Observables, and Option types all implement the same container-preserving transformation pattern, the author makes functional programming concepts immediately relatable. Understanding this fundamental pattern could remove a major barrier to learning functional programming and recognizing the underlying structure in modern JavaScript libraries.