I attended the World Wide Web 2006 conference in Edinburgh, Scotland last week. It was really interesting. Lots of knowledge on the future of the Internet. Here is what I learnt:
The first day I went to a workshop on tagging organized by Yahoo and RawSugar.
Tagging is the act of annotating something with a keyword. On the Internet anyone can tag. It puts the user in control. Tagging becomes useful when it happens on a large scale. Tags can be aggregated, organized into sets (like in flickr, youTube and technorati). A good tag set will cover as many facets as possible, e.g. music, artists, song, band, etc. People don't think "definition" when they tag. A tag can express an emotion, a insight, a gut reaction, anything. People are willingly telling us how they feel about something. That's part of the power. It's metadata for the masses.
Tagging works because it does not involve high brain functions of conscious sorting. It does not force people to make a choice (does skiing belong in the "recreation" or "sport" category?), things can have any number of tags. This kind of free, loose association is cognitively easy and makes less time. However, categories are arguably more memorable than tags, because you have had to make more of mental effort to add the category.
Tags can also count as opinion votes. Multiple instances of a tag are collected in bags of tags and determine how interesting a webpage, piece of music, photo, or any other tagable resource is (like in lastFM, My Web and delicious).
Tagging gives a sense of community. Like when playing a massively multiplayer online role-playing game like World of Warcraft, it gives a sense of "alone together". As described in the book, the wisdom of crowds, this leads to more cognitive diversity, less group-think, reduces conformity, reduces the correlated effects of individual mistakes, encourages new viewpoints, leads to less herd behavior and encourages participation.
Benefits of tags are:
- better search
- less spam / ability to identify genuine content
- ability to identify trends and trend setters
- a metric of trust
- ability to measure how much attention a resource is getting
- helps filter by interest (really works!)
Tagging is however limited in that people very rarely tag other people's stuff. Most tags are added by the content author. Tags are also often not very prominent, nor identified and collated in one's account.
Tags also lack structure and semantics. They exist in a large cloud, not an ordered hierarchy. Synonyms and polysemy can lead to a vocabulary explosion.
Search is a pull mechanism. Search engines need to go out an crawl the web to index all the content. This can take days. Tagging is push. Blogs notify the search engines when there is something new to to be had. Readers can be notified of new content the very second it appears.
It is difficult to add tagging to an existing system. Amazon tried this and failed. There has to be a clear role for tags. They have to provide some tangible benefit. The best tagging systems highlight unique contributions, give users control, allow for smaller tag-related sub-groups and allow for personalization.
Tagging can be described as going for a hike in the woods, or picking berries, while categorization is more like driving a car, or riding a rollercoaster.