Resumen
This article emphasizes the need for universal computer literacy. The pair of concepts "schema-- instance" has taken a predominant role in computer science (CS). Programs are schemata of a process. At runtime, instances are produced and are sometimes called threads of control. In database systems, conceptual schemata are designed, for example, relational schemata, under which tuples are subsumed as instances. Consider, for example, an employee relation as a schema and particular employee records as instances of that relation. This is a plea for universal literacy, the ability to comprehend the world through schemata, to mentally collect, design and redesign, and to generate instances from schemata. Today, the pair of concepts "schema--instance" is a domain of computer science, thereby establishing a significant contribution to the foundation of universal literacy. The point emphasized here is the insight that the pair "schema--instance" is not only indispensable when acquiring computer literacy, but the history of these concepts indicates the pair is of similar importance to the foundation of a universal literacy.