An electronic financial transaction system comprising: a secure terminal including a card reader for reading information from a customer's transaction card, input means for receiving user input relating to transactions, a display for displaying information to the user and communication means for communicating with a remote host via a telecommunications network; and a remote host system adapted to communicate securely with the terminal and with an acquirer system for processing electronic transactions initiated by the terminal; wherein the terminal includes a terminal application adapted to download and process code objects from the remote host system, said code objects defining functions to be performed by the terminal for the processing of electronic transactions by the terminal, wherein said terminal application includes an HTTP client capable of sending a conditional HTTP request with an identification of cacheable resources to the remote host system; and the remote host includes a gateway host configured to check each cacheable resource against records stored in a cache, and either returning to the terminal an update of the resource or confirmation that the resource is unchanged, said electronic financial transaction system being characterized in that if the gateway host receives no response from the cache, the gateway host sends a request to a configuration server, and wherein the configuration server is an HTTP server and processes the request by retrieving the required resource from a database for each cacheable resource, and returns the resource to the remote host system thereby configuring the terminal. a secure terminal including a card reader for reading information from a customer's transaction card, input means for receiving user input relating to transactions, a display for displaying information to the user and communication means for communicating with a remote host via a telecommunications network; and a remote host system adapted to communicate securely with the terminal and with an acquirer system for processing electronic transactions initiated by the terminal; wherein the terminal includes a terminal application adapted to download and process code objects from the remote host system, said code objects defining functions to be performed by the terminal for the processing of electronic transactions by the terminal, wherein said terminal application includes an HTTP client capable of sending a conditional HTTP request with an identification of cacheable resources to the remote host system; and wherein the terminal includes a terminal application adapted to download and process code objects from the remote host system, said code objects defining functions to be performed by the terminal for the processing of electronic transactions by the terminal, wherein said terminal application includes an HTTP client capable of sending a conditional HTTP request with an identification of cacheable resources to the remote host system; and the remote host includes a gateway host configured to check each cacheable resource against records stored in a cache, and either returning to the terminal an update of the resource or confirmation that the resource is unchanged, said electronic financial transaction system being characterized in that if the gateway host receives no response from the cache, the gateway host sends a request to a configuration server, and wherein the configuration server is an HTTP server and processes the request by retrieving the required resource from a database for each cacheable resource, and returns the resource to the remote host system thereby configuring the terminal. stored in a cache, and either returning to the terminal an update of the resource or confirmation that the resource is unchanged, said electronic financial transaction system being characterized in that if the gateway host receives no response from the cache, the gateway host sends a request to a configuration server, and wherein the configuration server is an HTTP server and processes the request by retrieving the required resource from a database for each cacheable resource, and returns the resource to the remote host system thereby configuring the terminal.