Fiber
Noun · Development
Definitions
A lightweight unit of execution that is cooperatively scheduled — the fiber explicitly yields control rather than being preemptively interrupted by the OS. Used in Ruby, Crystal, and React's internal reconciler (React Fiber).
In plain English: A super lightweight version of a thread that you control — it decides when to pause and let others run, rather than the system forcing it.
Example: "Fibers let us handle 100K concurrent connections because they're orders of magnitude cheaper than OS threads."