What are newsgroup search engines?

At launch the service had two innovations that set it ahead of the other search engines. It used a fast multi-threaded crawler (Scooter) that could cover a lot more Web pages than were believed to exist, and an efficient search back-end running on advanced hardware with many gigabytes of memory. These made AltaVista the first searchable, full-text database of a large part of the World Wide Web.