writing is the voice of

a person who is not present, Freud said. And it is well formulated. On the one hand, the printing press and the Internet liberated writing from the confines of time and place. As writing before distributed print was tied to an object, a stone slab, and/or in any case existed only in one version. On the other hand, the Internet made writing more or less ubiquitous, and todays' chat-programs can give you nearly synchronous written communication.
So, the oral language gave man a symbol system with which to reflect on and communicate about things not present. You can imagine and think about the lions of the tropical savanna even in the northernmost parts of the world. Then writing liberated language from time and place, and it could be the voice of the person who lived long ago or who lives on the opposite part of the globe.