What is it?
Have you ever bookmarked a webpage and placed it in a folder? Have you ever used a card catalogue? If so, you have already experienced the two major principles behind social bookmarking: categorizing and sharing.
Wikipedia defines social bookmarking well as "a method for Internet users to share, organize, search, and manage bookmarks of web resources". And, like the card catalogue, "the resources themselves aren't shared, merely bookmarks that reference them."
Social bookmarking is, in essence, an opportunity to make your own library catalogue of digital resources, share it with the world, and hook it up with other people's catalogues -- all via a dead-simple interface.
How all this works
In practice, this is a very simple process: as you browse the web, you look for pages of interest. When you find one, you save the location in your bookmarking service (usually with the click of a single button) and apply metadata to it. Typically, that metadata consists of a short description and one or more tags -- one-word identifiers or labels; think library of congress classifications, except you make them up yourself.
Like so much of the Web 2.0, the magic happens when many many people start doing this together. What was once a private collection of interesting links (not unlike the bookmarks you maintain in your browser), becomes a vast, searchable information landscape. Consider the advantages:
- Your bookmakrs are available from any computer on the internet
- You can share your bookmarks with anyone on the internet
- If you are looking for information on a topic, you can search by tag or keyword on everybody else's bookmarks
- Each bookmark has an accompanying count for the number of times it has been bookmarked by users, thereby indicating its popularity
The social bookmarking landscape
As of this writing, the social bookmarking landscape is dominated by two services: delicious and Diigo. They are closely related but slightly different services.