In Delicious there is not a specific tagging system as users are free to choose their own tags ie they can use any tagging mechanism. This leads to an unstructured method of aggregating favourite web sites. Moreover by using a tagging cloud, the most popular sites are highlighted. If researching specific topics this will not be useful as unpopular, specialised or new themes will not have obtained a good amount of hits.Moreover such a social bookmarking tool still needs users who are browsing (in a traditional manner) the internet. cos from this users will then tag their favourites.