a Web Directory is a collection of data or links if you will. It is organized into categories and subsequently into sub-categories to make it easier for both humans and bots to visit and find information, also through the use of keywords. Not all directories are created equal though. Some directories list absolutely anything while some are more choose and more “exclusive”.
Directories like DMOZ has very high authority on the wed and each entry needs to be approved by an admin, so you need to know how to list… or get denied… that is where we come in – the Pro’s!