Has a very large database and includes an advanced query form for very effective searches. Output is based on relevance and can be set to detailed, compact, or count format.
Documentation is helpful and includes good examples.
Boasts speed, and delivers, with a clear, clean usable interface, good results summaries. Has a large and diverse database, including the Web, Usenet, classified ads, or Web site reviews. You can search by concepts or keywords. Easy to use and powerful. Output is ranked according to relevance and can be sorted by confidence or site.