Written language and spoken language differ in several ways. Those differences affect subtitling, a practice that has become more prevalent recently as a way to translate what the speaker is saying for those of other languages or who are deaf. A key difference between written and spoken languages is that written language tends to be more formal and complex than spoken language. Other differences are: Writing is more permanent and less easily changed. Once something is printed, or on the Web, it is out there permanently. Unless the speaker is recorded, however, they can restate their position.