Accessible OCW ontology is designed to address accessibility need of OpenCourseWare systems. It is built on the accessibility Access for All (AfA) specifications of the IMS Learning Global Consortium which focus on describing learners' needs and preferences and educational resources annotation. The ontology uses and extends some vocabulary of the ACCESSIBLE to describe the disability types of learners on basis of the International Classification of Functioning, Disability and Health (ICF)


The ontology is composed of two main classes: Learner and DigitalResource.

  1. The Learner class describes the learners’ properties together with their needs and preferences. It is a subclass of the User class of the ACCESSIBLE ontology. We extended this class to represent the disability information; thus, we can deduce the needs of users from their characteristics. The properties are designed according to the IMS AfA Personal Needs & Preferences (PNP) specification (e.g., atInteroperable, accessModeRequired) .
  2. The DigitalResource class defines the properties of an individual educational resource. The properties are designed based on the IMS AfA Digital Resource Description (DRD) specification. They describe the resource access mode (e.g., visual, auditory) and define if resource has adapted versions (e.g., if there is an alternative transcript file to an auditory file). Furthermore, it defines other properties, like complexity of content, to provide authors the opportunity to offer a simplified version of the learning resource next to the normal one (isAdaptationof, hasAdaptation, atInterOperable, and languageOfAdaptation).