1. An electronic media distribution system arranged to insert secondary content into programmed primary content, said system comprising: a first database storing a plurality of primary content files, each of which contains primary content and has an associated identification code; a second database storing a plurality of secondary content files, each of which contains secondary content and has an associated identification code, said second database being separate from said first database; a first play list library storing a plurality of programmed play lists, each of which contains a sequential list of identification codes for respective primary content files which defines the order in which said primary content files are to be distributed, said programmed play lists only containing identification codes for primary content files; and a common server directly connected to said first and second databases and to said play list library, the server programmed to: receive a primary content distribution request; associate the primary content distribution request with one of said programmed play lists; and execute instructions which selects secondary content files from said second database and defines the frequency with which said secondary content files are inserted into the programmed play list associated with said primary content distribution request such that an integrated play list is generated comprising the primary content files associated with the programmed play list and the secondary content files inserted in response to said instructions, said frequency with which said secondary content files are inserted into said programmed play list being time based, in which a fixed time interval is defined and secondary content files are inserted into the integrated play list such that when said play list is played, a piece of secondary content will be played each time said fixed time interval is completed, or number based, in which a fixed value x is defined and secondary content files are inserted into the integrated play list such that when said play list is played, a piece of secondary content will be played after every x number of pieces of primary content are played; and two or more user interfaces, each of which is separate and distinct from and directly connected to the common server with no intervening network, each of said user interfaces arranged to: display a main activation menu screen through which a user may access the electronic media distribution system; display a series of selection menus through which said user may select content to be played; generate commands indicating the content selected by said user; and display the selected content for said user; said server further programmed to: provide data to said user interfaces for generating said main activation menu; provide data to said user interfaces for generating said series of selection menus; and, for each user interface, play the primary and secondary content associated with the integrated play list for the user via the user interface in response to commands received from said user interface, beginning with the first content file on said integrated playlist.