It is important to submit your site to good quality directories such as the Open Directory Project (DMOZ) and Yahoo Directory. This is because these are reputable directories that recieve alot of hits. They are also very important because they provide data to other directories such as DMOZ to ODP.
Search directories contain website listings that are ordered alphabetically and ordered by categories. Unlike organic search results, the websites that are placed into directories are put there by humans and the directory editors may also want to alter the title and description of your site to better suit their categories. Often, sites that are not substantial enough or which are inappropriate are refused entry into those directories.
It may help to point to the category on which your website is listed in these directories on your resources links pages because the websites in the same category as yours will also be of interest to visitors to your site. Such links are regarded well by search engines because they are relevant and useful so can therefore help rankings.
Google's directory takes its data from the open directory project and then ranks them according to pagerank. The open directory project provides directory listings to many other directories aswell such as AOL, AltaVista and smaller specialist directores. It is staffed by volunteers and therefore very slow to respond to submissions, therefore it is important to add your site to ODP as soon as it is complete.
Google often uses what you have submitted to the open directory project in the snippet information on SERPS. If your website is location specific then it should be submitted to the geographic location.
Yahoo charges around £200 and this guarantees inclusion within a set timeframe. It is therefore less difficult to gain access to. Not all sites however get accepted although a refund is provided if the website that you submit is not submitted.
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