So I have read that you only should have 3 levels of site structure. See below: Level 1: INDEX PAGE Level 2: Category Level 3: Sub-Page The reason being is that the search spiders will not search deeper than the 2nd or 3rd level in a site. So I read on the internet. But what if you have a site about cars. You could have so many levels of pages per each category. At what point do you stop?
you can have as many levels as you wish, search engines will index your site anyway, but maybe for 2-3 times.
The number of levels does not matter, as far as I have understood. The main thing, though, is that you have a clear hierarchy (i.e. www.whhop.com/cars/ford/mustang.html) which will enable the search to go more quickly and for the pages to carry more weight. It is also just good practice as far as site design goes.
Well my one site I'm working on is all just main domain/page1, main domain/page 2 as in only 2 level structure or teir 2