Open, Standards Based, Web Technology
The technologies used to produce content and interactive experiences that are mediated through the web browser.
For example: An app which runs within a browser is a web technology, something which requires installation on an operating system is not "of the web".
Any software which uses a license accepted by the OSI.
Any content that uses a license that appears in the Open Content Guide.
Any format that is specified by Open Standards
Any standard that conforms to the W3C or European Unions definition.