Invocational media are communication technologies based on digital computers. Invocational media infrastructures assign names (or addresses) to given entities (e.g. web pages with URLs, variables in programming, disk sectors with file allocation tables), and perform events to call up these named entities from invocable domains on demand (e.g. an HTTP request, a subroutine execution, a read or write to a hard disk). Term coined by Chris Chesher, Digital Cultures, University of Sydney, Sydney, Australia.