[fr] Les tags et les catégories, ce n'est pas la même chose. En bref, les catégories forment une structure hiérarchique, prédéfinie, qui régit l'architecture de notre contenu et aide autrui à s'y retrouver. Les tags sont spontanés, ad hoc, de granularité variable, tournés vers le partage et la recherche d'information.
I got a bit heated up last night between [Matt’s comment that tags and categories function the same](http://steph.wordpress.com/2006/02/09/give-us-real-tags-on-wordpresscom/#comment-182) and a discussion I was having with [Kevin](http://epeus.blogspot.com/) on IM at the same time, about the fact that [Technorati parses categories as tags](http://technorati.com/help/tags.html).
I went back to read two of my old posts: [Technorati Tagified](http://climbtothestars.org/archives/2005/01/14/technorati-tagified/) and [Plugin Idea: Weighted Tags by Category](http://climbtothestars.org/archives/2005/01/28/plugin-idea-weighted-tags-by-category/) which I wrote about a year ago. In both, it’s very clear that as a user, I don’t percieve tags to be the same thing as categories. Tags were something like “public keywords”. Is anybody here going to say that keywords and categories are the same thing? (There is a difference between keywords and tags, but this isn’t the topic here; keywords and tags are IMHO much closer in nature than tags and categories).
Here are, in my opinion, the main differences between tags and categories, from the “tagger” point of view.
– categories exist before the item I’m categorizing, whereas tags are created in reaction to the item, often in an ad hoc manner: I need to fit the item in a category, but I adapt tags to the item;
– categories should be few, tags many;
– categories are expected to have a pretty constant granularity, whereas tags can be very general like “[switzerland](http://technorati.com/tag/switzerland)” or very particular like “[bloggyfriday](http://technorati.com/tag/bloggyfriday)”;
– categories are planned, tags are spontanous, they have a brainstorm-like nature, as [Kevin explains very well](http://epeus.blogspot.com/2005_10_01_epeus_archive.html#113011082782089285):
You look at the picture and type in the few words it makes you think of, move on to the next, and you’re done.
– relations between categories are tree-like, but those between tags are network-like;
– categories are something you choose, tags are generally something you gush out;
– categories help me classify what I’m talking about, and tags help me share or spread it;
There’s nothing wrong with Technorati treating categories as tags. I’d say categories are a kind of tag. They are special tags you plan in advance to delimit zones of content, and that you display them on your blog to help your readers find their way through what you say or separate areas of interest (ie, my Grandma will be interested by my [Life and Ramblings](http://steph.wordpress.com/tag/life) category and subscribe to that if she has an RSS reader, but she knows she doesn’t care about anything in the [Geek](http://steph.wordpress.com/tag/geek/) category. (By the way, CTTS is not a good example of this, the categories are a real mess.)
So, let’s say categories are tags. I can agree with that. But tags are not categories! Tags help people going through a “search” process. Click on a tag to see related posts/photos. See things outside the world of this particular weblog which have the same label attached. Provide a handy label to [collect writings, photos, and stuff from a wide variety of people](http://technorati.com/tag/lift06 “The LIFT06 tag.”) without requiring them to change the architecture of their blog content (their categories). If you want to, yeah, you can drop categories and use only tags. It works on [http://del.icio.us/](del.icio.us). But have you noticed how most Flickr users have [http://flickr.com/photos/bunny/sets/](sets) in addition to tagging their photos? Sets aren’t categories, but they can be close. They are a way of presenting and organizing things for human beings rather than machines, search engines, database queries.
To get back to [my complaint that WordPress.com does not provide real tags](http://steph.wordpress.com/2006/02/09/give-us-real-tags-on-wordpresscom/), it’s mainly a question of user interface. I don’t care if from a software point of view, tags and categories are the same thing for WordPress. As a user, I need a field in which I can let my fingers gush out keyword-tags once I’ve finished writing my post. I also need someplace to define and structure category-tags. I need to be able to define how to display these two kids of tags (if you want to call them both that) on my blog, because they are ways of classifying or labeling information which I live very differently.
Am I a tag weirdo? Do you also perceive a difference between tags and categories? How would you express or define it? If categories and tags are the same, the new WP2.0 interface for categories should make [the Bunny Tags Plugin](http://dev.wp-plugins.org/wiki/BunnysTechnoratiTags) obsolete — does it?