A method of use of a data transfer system comprising an internet server and a communication apparatus, comprising the steps of: at the internet server: controlling the reception of data transmitted from the communication apparatus, the received data including identification data identifying selected content and user identification identifying the user of the communication apparatus; carrying out authentication of the user based on said user identification; extracting selected additional data from the stored additional data corresponding to the selected content data identified by said identification information; and transmitting said selected additional data corresponding to the selected content data to the communication apparatus; and at the communication apparatus: storing content data and a plurality of program lists associated with the content data; and transmitting the identification information of the content data to the internet server and receiving the additional data of content data from the internet server; the method being characterised by the steps at the communication apparatus of: controlling playback of content data by an external reproduction apparatus based on a program list so that the content data referenced in the program list is played back as a collection, the program list being associated with a predetermined identifier uniquely identifying the external reproduction apparatus among a plurality of external reproduction apparatuses; controlling presentation of the program list based on the additional data and accepting edits to the program list; determining whether an identifier received from the external reproduction apparatus is the predetermined identifier; and controlling transfer of the content data to the predetermined external reproduction apparatus based on the program list when the received identifier is the predetermined identifier. at the internet server: controlling the reception of data transmitted from the communication apparatus, the received data including identification data identifying selected content and user identification identifying the user of the communication apparatus; carrying out authentication of the user based on said user identification; extracting selected additional data from the stored additional data corresponding to the selected content data identified by said identification information; and transmitting said selected additional data corresponding to the selected content data to the communication apparatus; and at the communication apparatus: storing content data and a plurality of program lists associated with the content data; and transmitting the identification information of the content data to the internet server and receiving the additional data of content data from the internet server; the method being characterised by the steps at the communication apparatus of: controlling playback of content data by an external reproduction apparatus based on a program list so that the content data referenced in the program list is played back as a collection, the program list being associated with a predetermined identifier uniquely identifying the external reproduction apparatus among a plurality of external reproduction apparatuses; controlling presentation of the program list based on the additional data and accepting edits to the program list; determining whether an identifier received from the external reproduction apparatus is the predetermined identifier; and controlling transfer of the content data to the predetermined external reproduction apparatus based on the program list when the received identifier is the predetermined identifier. storing content data and a plurality of program lists associated with the content data; and transmitting the identification information of the content data to the internet server and receiving the additional data of content data from the internet server; the method being characterised by the steps at the communication apparatus of: controlling playback of content data by an external reproduction apparatus based on a program list so that the content data referenced in the program list is played back as a collection, the program list being associated with a predetermined identifier uniquely identifying the external reproduction apparatus among a plurality of external reproduction apparatuses; controlling presentation of the program list based on the additional data and accepting edits to the program list; determining whether an identifier received from the external reproduction apparatus is the predetermined identifier; and controlling transfer of the content data to the predetermined external reproduction apparatus based on the program list when the received identifier is the predetermined identifier. controlling playback of content data by an external reproduction apparatus based on a program list so that the content data referenced in the program list is played back as a collection, the program list being associated with a predetermined identifier uniquely identifying the external reproduction apparatus among a plurality of external reproduction apparatuses; controlling presentation of the program list based on the additional data and accepting edits to the program list; determining whether an identifier received from the external reproduction apparatus is the predetermined identifier; and controlling transfer of the content data to the predetermined external reproduction apparatus based on the program list when the received identifier is the predetermined identifier.