1. A computer-implemented method for effecting electronic commerce over a data network, the method comprising: receiving an initial block of data from a device; assigning the initial block of data from the device to a first server of a server system, the server system including a plurality of servers for performing load balancing, a session being initiated between the device and the first server, the first server being coupled to a first data cache and a database, information associated to the session being stored in both the first data cache and the database, the information associated to the session including an identifier for the session, and the first server having information related to a plurality of products available for purchase from an on-line merchant; generating a response to the initial block of data at the first server, with the response including information associated to the session; transmitting the response to the device; and causing subsequent blocks of data received from the device to be routed to the first server, with information related to at least one of the subsequent blocks of data stored in both the first data cache and the database, and with such information being stored as associated to the session, wherein at least one subsequent block of data is related to purchasing a product from the plurality of products in an electronic shopping cart corresponding to the device; and wherein the method further comprises retrieving information associated to the session from the database if such information cannot be accessed from the first server.