ConceptIsolated?Runs in Parallel?Memory SharingManaged ByLightweight?Ideal For
Process✅ Yes✅ Yes (true parallelism)❌ No (isolated memory)Operating System❌ NoHeavy, separate tasks
Thread❌ No✅ Yes (true parallelism)✅ Yes (shared memory)Operating System⚠️ ModerateConcurrent subtasks
Coroutine❌ No❌ No (cooperative multitasking)✅ Yes (same memory)Language Runtime✅ YesAsync I/O, lightweight concurrency

Use Cases

Use CaseUse Processes 🏢Use Threads 🧵Use Coroutines 🌀
Heavy CPU-bound computation✅ Yes⚠️ Maybe (GIL limits in some languages)❌ No (not designed for CPU)
Independent tasks (isolated memory)✅ Yes❌ No❌ No
Shared memory between tasks❌ Complex✅ Easy✅ Easy (same memory)
I/O-bound tasks (API, file, DB)❌ Overkill✅ Good✅ Best (lightweight)
High number of tasks (1000+)❌ Memory-heavy⚠️ Depends✅ Excellent (cheap to spawn)
Multicore parallelism✅ Best choice⚠️ Depends on language GIL❌ Not for true parallelism
Real-time responsiveness⚠️ Slow startup✅ Yes✅ Yes (esp. async I/O)