Literacy refers to the use of the written word, as opposed to orality, which relies on the spoken word. Literacy arose with civilization, and many regard it as one of its defining characteristics. With its collapse, literacy has all but disappeared. Only a handful of communities and have preserved it.
In a literate society, the word enters the visual field and communication takes on a distinct “thing-ness.” Where oral societies experience learning or the exchange of information in the context of discussions and social relationships, literate people experience learning from objects like books. Even when the “objects” become more abstract (e.g., a website), they retain the basic nature of a discrete block, rather than a connected, continuous process. This trains literate people to focus on things rather than processes, and taxonomy and classification rather than relationships.
Beyond civilization, this frame of mind became a serious hindrance. Where oral trackers could more easily notice the relationships between one sign and the next, and the continuous process of the trail itself, literate trackers often had to make a conscious effort not to dwell too much on the individual discrete tracks and signs that they found.
In the Rusting Ages, dogmatic literalism and notions of how to classify people into a taxonomy created enormous tension and friction, problems which proved the difference between survival and extinction for many communities. As the world transformed, the information preserved in written sources became less and less relevant to daily life, so the cost of literacy increased as its benefits severely decreased. After four centuries of this, literacy became all but lost.
Nonetheless, a few communities do still preserve literacy, often as part of a special custom that a few initiates take on. Some groups like the Vulture Priests preserve literacy as part of their mission. Often these groups look at literacy as a sacrifice that a select few make for a special purpose. They recognize how learning to read changes the way a person thinks and perceives the world, and that this transformation can make it more difficult for them to relate to others as most people do. Those who learn to read accept a degree of alienation from the world in order to achieve some necessary purpose.
Preserving written records presents a number of challenges. In the tropical climate that has enveloped the whole world, document preservation becomes even more difficult. Archivists have developed some techniques to fight against this particular form of entropy, like encasing important documents in transparent plates made from hagfish slime.
If one can preserve the documents, then one can read the words as someone else wrote them generations earlier. This can lead to problems in reliability of their own, such as disputes over literalism and understanding archaic language when the meaning of the words used in the document have changed over time.