What other methods of goroutine synchronization exist in Go besides channels?

In addition to channels, in Go, you can use the following for goroutine synchronization:

• sync.WaitGroup — allows waiting for a group of goroutines to finish.
• sync.Mutex — a mutex for protecting shared resources from concurrent access.
• sync.RWMutex — a mutex with separate read and write locks.
• sync.Cond — a condition variable for notifying goroutines about an event.
• atomic operations from the sync/atomic package — for atomic operations on variables without locks.

Example of using WaitGroup:

var wg sync.WaitGroup
wg.Add(1)
go func() {
    defer wg.Done()
    // goroutine work
}()
wg.Wait() // wait for all goroutines to finish