The main difference between search and routing is that the search process matches a single Detection Need against the stored corpus to return a sub-set of documents whereas routing matches a single document as it enters the system against a group of Profiles to determine which users are interested in the document. Profiles, therefore tend to be standing and long-term expressions of user needs, whereas search queries are typically ad hoc in nature. A generic detection architecture can be used for both the search and routing. Each of these tasks is discussed separately below, but the similarities should be apparent both in the figures and in the descriptions. Search Search is the retrieval of desired documents from an existing corpus.
Retrospective search is frequently interactive.
Some methods also analyze free text Detection Needs to allow comparison with the indexed corpus or a single document. Search can be understood in terms of a set of modules shown in Figure 1. Any particular document detection system uses own set of modules which may vary slightly from the ones described below. A corpus is comprised of the source documents from which the user will select the document sub-set. The content of the corpus may have significant the performance in some applications.