Explain interfaces in Go and how they work.

Interfaces in Go: • Define a set of method signatures • Implemented implicitly (duck typing) • Enable polymorphism • Can be empty (interface{}) • Support type assertions • Enable dependency injection Example: type Writer interface { Write([]byte) (int, error) } type File struct{} func (f File) Write(data []byte) (int, error) { // Implementation return len(data), nil }