"Foreword This document (prEN 16426:2012) has been prepared by Technical Committee CEN/TC 353 ""Information and Communication Technologies for Learning@ Education and Training""@ the secretariat of which is held by UNI. This document is currently submitted to the CEN Enquiry. This document presents an Application Programmer Interface (API) for querying learning object repositories. The core is an abstract API; bindings to web services@ Java and PHP have also been developed. Since one major design objective is to keep the specification simple and easy to implement@ the interface is labelled Simple Query Interface (SQI). In the context of this document@ learning object repositories are defined as collections of educational material@ courses@ and learning objects with associated descriptions (referred to as ""metadata""). Examples of repositories for learning are educational brokers@ knowledge pools@ streaming video servers@ etc."