Abstract: A system for the transmission and reception of data by telephone line, the system making use of the idle time on the telephone line, which connects the switching system of a telephone exchange with the telephone in a user's home, to transmit signals by way of the telephone line from a center independent of the telephone exchange to the user's home. The center includes a data base for storing a plurality of items of compound data, each item consisting of a specified number of interrelated data groups, and a transmission unit which accesses the database, reads data groups in order from an item of compound data, converts the resultant digital signals to analog form and outputs the analog signals to the telephone line.