Why use categories instead of tags?

(Patrick Klug) #1

I’m just curious on what the rationale behind going for single categories instead of tags is. On SE tags seem to work well, at least from a users perspective.

(Jeff Atwood) #2

This has been covered a … number … of times already, but:

  1. User tagging does not work very well beyond tag #2. Everyone can tell you a question is Java and maybe that it involves I/O but beyond that… super noisy.

  2. Keep It Simple. One category, for large obvious easily explained distinctions, not tiny complicated subtle inscrutable distinctions. (We do have a plan to add sub-categories in the near future, but we want to keep it simple.)

  3. In forums, historically categories (sub-forums) are often used to wall communities off from each other and divide warring factions. Trust me, you really don’t want to be in the Politics & Religion category. Or the Android category if you’re an iPhone user… etc.

  4. We believe categories should be optional to start with. I hate being slammed in the face with the Dewey Decimal Catalog system as the home page of every forum ever. Don’t give every new arrival a PhD in your particular local definition of Animal, Vegetable, or Mineral by forcing them to select a subforum when they arrive. Just show me what the heck is actually being discussed here already, man!

  5. Categorizing things is best done by moderators and very experienced users only. That’s why we kept increasing the minimum reputation on Stack Overflow required to create a new tag over time… because new users would create insane, worthless tags non-stop.

  6. We originally allowed an unlimited number of tags, then immediately realized this was terrible mistake when we saw people “tagging” with every word of their post. We limited to five tags… I now think that was about 3 too many.

A totally free for all wild west everyone can tag everything system does not actually work that well, just browse around meta.stackoverflow in the tagging areas.

Handling large numbers of categories with subcategories
Category Conundrums Two Deep
Why was the Latest page chosen as the landing page?
(Juan Manuel Formoso) #3

Awesome points!

Subcategories would be neat though. We are currently trying to use discourse as our internal discussion platform, and we have 4 or 5 “verticals” to which every application belongs – it would be super useful to be able to have the main category as those 4 or 5 super groups, and then group them by application.

(Jeff Atwood) #4

Great post by a large community moderator on the pitfalls of over-categorization, something we explicitly try to avoid:


Over specialising categories is a common problem that manifests itself differently in communities old and new. It most commonly manifests as a gigantic front page, filled with every possible permutation of the community’s general topic. A community about games might have separate categories for first­person shooters, third­person shooters, side scrollers etc, where they would better be served with either a category marked “Shooters” or simply an overarching category marked “Games”.

In new communities, this stems from a desire from the founder to make sure that any topic the community could want to talk about is covered. While this is understandable, it will lead to users simply being intimidated by the enormous number of categories at their disposal. In most communities with vast numbers of categories, the majority of them will lie fallow. If a new user posts in one and doesn’t get a response, they’re unlikely to persist much further.

In old communities this is simply the result of gradual category­ creep. For example, any general discussion community will sooner or later have users asking to create a whole category based around the more popular threads. Sometimes these are topics that can sustain their own category easily. At other times, these will be fields that are sufficiently specialist that you would simply be shunting the dozen or so people who already post in the relevant threads into a category on their own, where it will become obvious that the topic does not have enough interest to sustain it. These categories will either die out, or loll around for years with a few dozen posters, becoming increasingly cliquey over time.

Categories vs. tags
(Dan Dascalescu) #5

This is an excellent point if the user is completely new to the matters discussed on the forum, so it will apply to casual surfers. However, such users will likely land from a search result and perhaps reply or post a new topic in the same category, so categorization matters less.

More commonly, users are familiar with at least several categories in the forum and may prefer a category-centered view. I’ve expanded upon that in:

My feelings on the landing page aren’t very strong though.

My biggest problem with categories is that they don’t map real epistemologies very well. Information/Revolution by Prof. Michael Wesch of The Machine is Us fame describes the problem very well:

Say you want to discuss the correlation between sleep and weight loss on a health forum. Instead of posting in one of the categories and perhaps cross-posting in the other, why not tag the topic with both tags? By the way, the mere existence of cross-posting is a sign of the limitations that categories artificially impose.

Practical question: how would a Discourse forum with only tags and no categories work? Is there one out there?

(Sam Saffron) #6

We have a forum that only uses tags and it works quite well … see: http://forum.gethopscotch.com/ cc @anon73622809


Apart from being useful when you have a post that falls into several different topics but doesn’t belong to one in particular, like @dandv said, I find having tags rather than categories is also useful when you’ve got a post that doesn’t belong in any existing topics, so users can add in a new tag if it suits. (CC @Liza_Conrad and @Asha_Gupta)

(Ratul Bhattacharya) #8

@codinghorror: I have a question on this. I am trying to run a discourse for a stock market which will broadly have many listed stock. Each stock can have different kind of operations like long term purchase short term, divident etc. My question is more around design and how Discourse fills it in. Should all the listed stocks be considered a category? meaning if I have 1600 stocks then should I have 1600 categories? Please advise

(Sam Saffron) #9

I would recommend against that, instead add categories for “sector” and then use tags for stock code.

(Ratul Bhattacharya) #10

thanks @sam : Thats a good idea. let me try that out.

(Stefan Brand) #11

It seems that 2.5 years later there are actually categories in that forum:

@anon73622809 Was it like this before? If no, what made you move to categories?


Hi Stefan, we switched to categories around April 2017

The actual problem was a little more complex… off-topicness. (I am not working there anymore, though as an avid member of that community, I have to say I’ve learnt a few things).

(Stefan Brand) #13

This sounds like at least a minimum of categories are actually essential.

We are discussing a new category structure of the Fairphone Forum at the moment. We will probably go from 8 “descriptive” super-categories with 17 sub-categories…


…to 4 “engaging” super-categories with 10 or 11 sub-categories:

  • Help
  • Discuss
  • Participate
  • Buy/Sell

(Stefan Brand) #14

And here is the new structure of the Fairphone Forum:

Edit: Screenshot