Abstract: A self-evolving generic index for storing marketplace information for multiple types of items allows users to add new parameters, values and possibly new classifications for use in describing items. The new parameters/values/classifications can then be selected by other users for use in describing their own items. It is especially contemplated that the system can display information relating to the usage with which parameters/values/classifications have historically been employed in describing different types of items. This encourages users to be consistent in selecting parameters/values/classifications for both entering and searching data, while still allowing great flexibility.