social tagging
The internet is a big place, and to make it a bit easier to find useful things we now have social tagging. This is where pages, photos, videos and other online content can be classified by the users themselves rather than a bit of software or the website's producers. Schools are starting to use free sites like Delicious, YouTube and Flickr to their advantage.
bookmarks
Delicious uses social tagging to store and share bookmarks. You can click a button to bookmark a site you like, whether you are at home or at school. You then type in words to classify the site or choose from suggested tags that other people have already used on that site. This lets you have a list of bookmarked sites, even if you use lots of different computers. You can give your students a link to a page listing all your bookmarks which have a particular tag so that they can use it for revision.