Green Threads
Green threads are user-level threads managed by a runtime or virtual machine, rather than the operating system kernel. They provide lightweight concurrency within a single process, allowing multiple execution flows to be scheduled and switched efficiently without kernel involvement. This enables high-performance threading in environments where kernel threads are too heavy or unavailable.
Developers should learn about green threads when building high-concurrency applications in languages like Java (early versions), Go, or Erlang, where minimizing overhead and maximizing throughput is critical. They are particularly useful in I/O-bound scenarios, such as web servers or network applications, where many tasks can be managed with low resource consumption compared to kernel threads.