17. A terminal device comprising: a transmitter for transmitting information to a service providing device; control means for transmitting, wherein said control means transmits, to said service providing device via said transmitter, specification information specifying at least one of an electronic document without a tag and a tagged electronic document tagged according to a markup language, and transmits request information indicating a request for a tagged electronic document including a tag indicating a structure of the electronic document without a tag; and a receiver for receiving, wherein said receiver receives the tagged electronic document which is transmitted from said service providing device in response to said request information and said specification information, wherein if said receiver receives data from said service providing device indicating that no document corresponding to the transmitted specification information is stored in said service providing device, said control means transmits said electronic document to said service providing device via said transmitter.
19. A terminal device according to claim 17 , wherein said control means transmits a keyword included in an electronic document as said specification information to said service providing unit via said transmitter.