This is my first question, so please be gentle with me :). I have tried to search for the answer, but I don't really know what the thing I'm after is called so can't formulate a decent search query.
I'm after making the input forms on a database of online resources as user-friendly as possible, to encourage users to add some decent metadata, in particular tags (keywords). I very much like the Wordpress and Flickr approach to adding tags, where you attach tags in an input field and they appear below the field with a 'X' beside them for users to 'un-attach' tags from the record. This is plainly an Ajax operation, but without some serious source code digging I can't figure how it works. If anyone knows what I'm talking about, could you suggest an algorithm or even a search term to use, as I'm not sure what these things would be called - Ajax tags, perhaps? I did search for "Ajax tags" but got heaps of results, and couldn't see anything relevant in the first few pages.
I'm using PHP and mySQL on the server, jQuery on the client.