The Global Electronic Business Directory
This type of engine uses a robot or spider which constantly roams the World Wide Web searching for new or updated pages. When the robot visits a page it reads the whole thing, including any sub-pages on the same server connected to the page it's reading, then it visits all the external links on the pages it's read.
Don't be put off by the heading, these are often more useful than the deep engines for finding useful, relevant information on general or popular topics. The only information held in the database is what is input by the people registering their pages using input forms provided by the administrators of the engine.