1. Addressable units of information that are addressed through Uniform Resource Identifiers (URIs). 2. The early notion of static addressable documents or files has evolved to a more generic and abstract definition. Every ‘thing’ or entity that can be identified, named, addressed or handled in any way whatsoever in the web at large or in any networked information system. Examples include: an electronic document or data stored on the Web, an image, a service (e.g., “a weather report), a collection of other resources. Each resource must have a URI.