Since the internet started, directories have been created to help people find the information they are looking for – think of online directories as simply an internet-based version of the Yellow Pages.

Online there are directories that are very broad covering lots of topics, and there are directories covering very narrow or niche areas. An example of two broad directories are the SuperPages in the US or YellowPages in Australia. And an example of a niche directory is Twellow.com - this is a directory of Twitter users.

Listing in directories can be free or paid or they can be both with different benefits assigned based on whether you pay or not. For example YellowPages Online in Australia is free to list your business name, phone number and address but it doesn't include a premium position for your listing (i.e. first page), bold text, website listing or multiple phone numbers.