1. A method of identifying a subset of data from a selected web page of a web site for display on a client machine, the method comprising: applying one or more instructions to the selected web page for identifying and displaying a candidate subset of data on the client machine, the instructions applied in accordance with one or more pre-defined criteria defining one or more types of the subset of data, and one or more pre-defined confidence intervals defining a pattern for locating the subset of data in accordance with said one or more types on the selected web page.