Explain the context package and its use cases.

Context Package: • Carries deadlines, cancellation signals, values • Request-scoped values • Cancellation propagation • Timeout handling • Standard library integration Types: • context.Background(): Root context • context.TODO(): Placeholder • context.WithCancel(): Cancellation • context.WithTimeout(): Timeout • context.WithDeadline(): Absolute deadline • context.WithValue(): Carry values Example: ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second) defer cancel() req, _ := http.NewRequestWithContext(ctx, "GET", url, nil) resp, err := client.Do(req) Best practices: • Pass context as first parameter • Don't store contexts in structs • Use context.Value sparingly • Always call cancel functions