Why do some people prefer Stack Exchange to Quora?

I use Stack Exchange when I have a question that can easily fit into one of Stack Exchange's mini niches.  This most often comes into play when I have specific computer science questions.  Stack Overflow (a niche of computer science related questions inside Stack Exchange's network) has an incredible user base devoted to answering questions quickly and accurately.  I would rather ask a computer science question on Stack Overflow than on Quora because Stack Overflow is an entire separate community within Stack Exchange built around answering computer science questions.  However, if I can't find a suitable niche within Stack Exchange to ask my question, I turn to Quora. I also find that I use Stack Exchange to discuss questions requiring factual answers, and Quora to discuss questions more opinion-based.

If there's an Stack Exchange site covering your topic, it's much more likely to get answered quickly on Stack Exchange than on Quora. For answerers, some like getting "high scores" answering questions which Quora doesn't really focus on. (Update: Quora does have credits now, which is somewhat similar to Stack Exchange points.)

I have spent a fair bit of time on multiple Stack Exchange sites, and I second everything Qiaochu says in his answer. The focus of each Stack Exchange site, as I see it, is to provide correct, useful answers to to precisely answerable questions on the topic of that site, be useful not just to the person who asked it, but (as a secondary goal) build a high-quality base of questions and answers that would also be useful to anyone else who arrives at the same question through search engines. Everything about the Stack Exchange design and culture is (intended to be) in service of that goal. There is a focus on eliminating cruft and keeping only good quality -- the goal from the very start was to be the opposite of Yahoo Answers (http://theyahooanswers.tumblr.com/) or http://en.wikipedia.org/wiki/Experts-Exchange and so on. If someone's answer has a mistake, or they make unsubstantiated statements of opinion, people will challenge the claims in the comments below the answer, or downvote it. Remember that a faulty answer affects not just the person who asked the question, but whoever else possibly months or years from now has the same question. Not that this doesn't happen on Quora, but there is less of a concern here with every line in every answer having to be factual. Questions have votes, and are relatively well-organized by tags. If I look at http://math.stackexchange.com I see only math questions, and I can further filter it by tag (say elementary-number-theory or combinatorics), and further focus on only the questions with high votes and low number of answers (say). The good questions are truly more of a pleasure to answer, you have more of a feeling that you are helping someone who has already done their best effort and truly needs to know. Quora does not allow voting on, or show statistics on questions; it does have "topics" but these are rudimentary; not enough effort seems to be devoted to categorization and cleanup. And I can't even find a way to see a list of questions; the Quora front page is a "feed" or questions and answers interspersed in no particular order (reminiscent of *shudder* Facebook). Closing duplicates is attempted -- even when you first try to ask a question, Stack Exchange (henceforth "SE") shows you related questions, and you are expected to have first made some reasonable effort to ensure your question has not already been answered. When the same question appears in multiple places, the answerers' efforts are wasted, or someone wanting to know may get wildly different quality of answers depending on which question they land up at. The goal is to have one canonical list of answers for that question, sorted by usefulness. On Quora I have not so far seen questions being closed as duplicates (or for any reason!); in fact I have seen duplicate questions. Everyone who has gained sufficient "reputation" on SE is given the ability to do some janitorial work (vote to close bad questions, edit tags on questions, or even edit bodies of questions and answers) -- such basic janitorial work is often missing here. On answers, the number of upvotes is displayed prominently (and you can upvote or downvote anonymously; the only consideration being the merit of the answer), so that anyone looking at the question knows that at least N people thought it was a correct and useful answer to the question. (Not that they liked the answer, or that the answer was funny or interesting: such answers are generally discouraged and preferred as comments, not because members don't have a sense of humour, but because they realise it doesn't help the goal of having the most useful answer be at the top. Newcomers often mistake this, which is why SE has ironically adopted it as a motto: "We hate fun".) Quora doesn't have this focus; a witty comeback to an annoying question may well be the highest voted answer here. In fact, the list of close reasons for a SE question (see http://stackoverflow.com/faq#close and http://stackoverflow.com/faq#dontask ) are good indicators of the site's philosophy: questions that are exact duplicates, that are off topic (here on Quora nothing is off-topic), that require arguments and extended discussion rather than facts and references, that are vague or rhetorical, and that are "too localized" ("unlikely to help any future visitors") all get closed on SE. Here on Quora anything goes. While I realize some people would like this, to me as Qiaochu says it is more satisfying to answer questions where I can objectively see whether I have a good answer or not. Here on Quora you see all sorts of questions that have no factual answers: "What does it feel like to X?", "Why do some people Y?" (like this very question), "What do Z people think of W?", etc. All these questions would be closed quite quickly on most SE sites. Nothing bad about any of them, of course, and closing a question doesn't mean that the asker is a bad person or is disliked; just that such questions are not part of the mandate of the site. Quora sends me too much email by default, and like Qiaochu for a long time I ignored it as some spammy website. The default settings on SE are to not send email. As I write this very answer, I don't feel very comfortable. I'm making statements of opinion that may not just be wrong, but which I myself may not share in a few months. It makes me uneasy; and the fact that there's less of a guarantee that someone will show me where I'm wrong makes it more uneasy. :-) Or, you could ignore everything I wrote above, and watch the following. Here is a talk Joel Spolsky gave on the Google campus recently, explaining some of the design decisions that have gone behind trying to influence the culture of Stack Exchange websites. Somewhere towards the end of the talk, in answer to a question he describes Quora as being more like "provoked blogging". This seems a good description of the difference between the two websites: any question goes, and the point of the question is more to provoke good answers (questions are valuable if good answers result; they don't have to be genuine problems that someone is facing). So Quora attracts both people who want to solve interesting problems and help others, and those who just like giving out their opinion on things. Quora answers are not necessarily objectively high-quality answers, but more like blog posts that may gain appreciation or not depending on emotional appeal, style of writing, etc. Edit: See also http://blog.stackoverflow.com/2012/01/the-trouble-with-popularity/ which includes this quote from Reddit: The problem with image macros and rage comics [...] is that they’re quick and easy to digest, and thus tend to get upvoted faster than self posts and actual discussions which take thought and time before an appropriate response can meted out. And Quora tends to promote exactly this sort of content.

Apart from other reasons that people mentioned here, 1. Anonymous upvotes -> You upvote an answer simply on its merit, rather than because it appeared in your feed  / was answered by a 'celebrity'. 2. Dumb/unanswerable questions are closed immediately. Mostly people are supposed to do some prior research before asking a question. 3. Upvote/downvote for the questions too! Helps to find good questions.

I generally participate on the science sites. I like reading Quora, though I haven't tried contributing much. I may start soon, though. Why do I like SE more? More login options. SE has its own login, as well as OpenID support (well, its own login is OpenID as well) Your content isn't by-default "hidden" to the world (unlike Quora's "login to see more answers"). If I write an answer, I write it for the benefit of the world, not just the asker. In fact, on SE, questions which aren't of much use to others are closed. Great, focused questions that lead to great answers which you learn a lot from. While Quora has a lot of fun stuff to read, when I want to learn physics, I prefer http://physics.stackexchange.com. There's too much opinionated discussion on Quora for this purpose. In other words, a better signal-to-noise ratio in the context of learning new tings. Communities with a lot more experts interested in writing good answers. And the non-experts still take the site seriously. Moar science, less lolcat. Fun meta. The http://meta.stackoverflow.com is a lot more Quora-like in that it invites discussion and is a fun place to goof around.

The 10 reasons why I prefer to use Stack exchange to Quora are : <*Be informed, these are my personal view why I give preference to SE than Quora.*> 1) I will not get distracted by other topics and threads. Quora is having distracting GUI and questions are interesting, so I easily get tempted and spend more time in reading other threads and finally end up in losing my intention of coming to Q&A site. 2) Higher visibility : Everybody on the web can see my question and get answer for thier search request in Google search, no login account is required. 3) When I have a problem and search on Google, SE and wiki comes in Google search 1st page but not Quora. 4) Quora answers are user's views, perceptions and their experience. It is not the technical or scientific truth/view. Quora answers differs for community, person, culture, etc. Quora is like a place for knowing the user's perception. I could able to get the same/better answers in Wiki and SE than Quora for a problem. Here people are inputting their views/facts which really doesn't need to be true always. 5) Quora is Q&A site more like Facebook. SE is Q&A site how it suppose to be. Q&A site should not give social network feel. The reason why Quora is giving such feel is users are asking clarifications, responding to others answers and making statements with own personal experience. SE questions are precise if you find a question you need in SE, mostly you will get an answer and able to resolve your problem, But here you will get only individuals views not answers. "SE answers portrays what is the answer to the question, Quora answer portrays what people thought for the question". 6) In SE discussions, useless comments are not entertained and they are  moderated, But not in Quora. In Quora most questions are asking users opinion and like a survey. Ex "Why people hate XXXXX" , "What it is like XXXX", "Why people use XXXXX". Person asking a question on SE are made to do the basic research before posting it, But not the case here. 7) SE is having different sites concentrating for different category, but Quora is clumsy. So Quora is entertaining like social network by reducing its quality. SE is particular in quality and categorizing. So people tend to use more and follow SE to get latest updates/trends in that site.  Quora is a place for everyone, But SE is place for people who are interested in that site. You can play in Quora forever even if you do not know anything, But You cannot spend more than 10 minutes in SE if you don't know that particular site content. 8) SE users are always having the fear of losing their hard earned reputations when they do something silly/mischievous things in SE. But nobody cares Quora credits. Badges/reputations are the tools to open the features. And these badges/reputations are like a college degrees, qualification and status. You can get to know the high level idea about users profile/knowledge with their reputations but not with Quora credits. So you can take Reputation = knowledge, credits = nothing but a number. 9) SE reputations are hard to earn if you do not have knowledge on that particular stream. But In Quora You get up voted when it is favor of larger community. Nobody cares the authenticity or truth of the answer or comments. Quora up votes are like Facebook likes, You will get more if you able to attract the user. 10) No moderators to correct the Quora content. SE moderators maintain the quality of questions, answers & comments and so ensuring correct valid output is given to public. But Quora edits are not being used much. In SE you will straight forward slap with a down vote when you do silly things, so people will have fear of giving proper precise content.  Moderators block the thread if content is inappropriate. In Quora, funny and entertaining threads are more famous than knowledgeable threads. Sit with pop corns and read Quora threads, easily you can spend two hours, which you cannot do with SE. If Quora is going like this, then It will be like an another Yahoo Answer in near future

I actually greatly dislike Stack Exchange due to the elitist, deletionist culture of most SE sites. I'm an experienced software developer and computer user and my carefully-composed, painstakingly edited questions routinely get moved (and thus killed), put 'on hold' (and thus killed) because they might be moved, and so on. That being said, there is one reason I put up with the abuse for so long before turning to Quora: Stack Exchange doesn't require me to sign in to view content, and Quora does. That is the primary reason I haven't created a Quora account until now. The secondary reason is abuse of search engines, where the search engine sees all the content (thus providing Quora with inbound traffic), but the user must sign up to see the content which the search engine can see freely. Experts Exchange and similar spammy tech-answer sites do this by putting the question at the top, with a big "sign in to see the answer" below, and then a 5000px high footer full of ads and garbage, but the content is readable if you just scroll to the bottom. Quora is more unethical, actively preventing the casual search engine user from deriving value from the time they spent to click the link. Unfortunately, I've had to renounce my refusal to use Quora over the issue because the attitude and definition of "on-topic" on most Stack Exchange sites is so unbelievably god-awful.

In addition to what is mentioned in the other answers: In StackExchange, you can follow new questions in each topic (or combination of topics) using an Atom feed. Quora does not have a similar feature. There is a topic feed, but it is a feed of "Top Answers", rather than new content. Therefore, it is much follow topics on Quora through a feed reader.