Go: What is the difference between goroutine and thread?

Goroutine — lightweight. Thread — OS-level.

Stack:

• Goroutine: 2KB (dynamic).
• Thread: 1-8MB (fixed).

Scheduling:

• Goroutine: Go runtime.
• Thread: OS kernel.

1go func() {
2    fmt.Println("Concurrent")
3}()

When to use goroutines:

• I/O-bound concurrency.
• Background tasks.

When to use threads:

• Cgo interop.
• Thread-local storage.

Common mistakes:

• Not synchronizing completion.
• Closure variable capture.
• Assuming goroutines are parallel.
• Creating too many without backpressure.
• Using runtime.LockOSThread() unnecessarily.