1. A method of processing a source set of raw events of unknown event types to a target set of typed events, each raw event being a package of data items containing data values of detectable data types, comprising the steps of: (a) providing a library of event type objects each of which relates to a given event type and contains a structured set of attributes of given data types; (b) for each raw event, determining at least one event type object in the library which meets the following criteria: the data items of the raw event can each be mapped to one of the attributes of said event type object, and the detected data types of the raw event each match the given data type of the respective attribute mapped; and (c) generating a typed event from said raw event by structuring the data values of the raw event in the form of the event type object determined.