I need to get working on a website where registered users can edit any content that is on the website ( like a wiki). I have to make it work like a directory, say like yellow pages or a telephone directory. Any user who registers, can simply open up a category, like a city or a particular thing like say auto spares and edit the page to enter the required information. I am staying away from using a wiki because that would require users to go through the entire source of the page when they edit it and abide by the wiki markups. Is there any way by which I can achieve this using Drupal. I have basic knowledge of PHP.