written communication
written language
black and white

His very ignorance of the usual written language helped him.

Whichever, it was not like any written language she had ever seen.

But in the course of the last ten thousand years, we have developed written language.

He is often called the "father of the Finnish written language".

"They have no written language, and I cannot hear their sounds," she said.

This written language was a more or less uniform system until the mid-20th century.

We are often described as a people with no written language.

Soon, he too had grasped the human written language and was able to read them himself.

You're coming from a world that doesn't even have a written language.

The Indians are using the excuse that they didn't have a written language.