The QueryTracker (the search engine submits the user’s query daily and returns the answers – the Web pages that have changed since the previous search or the new ones). The magic in QueryTracker comes from its automatic generation of an additional daily query, based on what it learns about the user’s interests and priorities over time.

QueryTracker’s ability to generate its own searches can compensate for the poorly formed queries that many users write. The most common mistake is that the queries are too short.

Another new direction is the “focus crawler”; making indexes only pages related to the specified topics and then tailors the rankings to the interests of the user. The crawler would get progressively better at building its nightly index by observing the behavior of the searches against it.