well put in the flickr blog:
Many hands make light work "Have you ever tagged someone else’s photo? I know I have. A describing word, or perhaps even two joined together; a ‘lasso’ to group photos together from an event; identification of a subject in the photo; a colour; a season…
All that work that we’ve put in has contributed to making something greater than the sum of its parts: an organic information system, derived of descriptive words and phrases made entirely from individual contributions. You can see what’s going on in the world by watching
hot tags fly by on our main tags page. You can even see what’s going on now in some of the bigger cities in the world on our
new Places pages. All thanks to the determined effort of you, you nerdy taggers, you.
There are about 20 million unique tags on Flickr today. 20 million! They are the bread and butter of what makes our search work so beautifully. Simply by association, tags create emergent collections of words that reinforce meaning. You can see this in our clusters around words like
tiger,
sea,
jump, or even
turkey.
What if we could lend this wonderful power to some of the huge reference collections around the world? What if you could contribute your own description of a certain photo in, say, the Library of Congress’ vast photographic archive, knowing that it might make the photo you’ve touched a little easier to find for the next person?
Well… you can. ..
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