The search engine originally created as a web directory by two Stanford PhD candidates was Yahoo.
Yahoo began in 1994 as “Jerry and David’s Guide to the World Wide Web,” a directory assembled by Stanford students Jerry Yang and David Filo. Rather than automatically crawling and ranking the entire web, the early service organized websites into human-selected categories, making it easier for people to browse the rapidly growing Internet.
The name Yahoo originally stood for “Yet Another Hierarchical Officious Oracle,” although the founders also liked the word’s ordinary meaning. Yahoo was incorporated in 1995 and became one of the early web’s most prominent portals, expanding beyond directory listings into email, news, finance, advertising, and other online services.
The key distinction is between a web directory and a crawler-based search engine. AltaVista and Google became known primarily for automatically indexing webpages, while Yahoo’s first identity was editorial organization by category. Yahoo later incorporated conventional search technology as the web grew too large for manual cataloguing alone, so its modern search services should not be confused with its original directory format.