Adam D'Angelo

We started off by inviting our friends to use Quora, and then they invited their friends, and it just grew from there.

I really like knowledge and reading books and just generally immersing myself in information.

Lawyers and other professionals are using Quora to build their reputation and build their bonafides.

The more questions and answers we get, the more useful Quora is.

I think a lot of what the iPad app is going to be used for is just reading the best content on Quora. It really helps the whole system run because people who are writing answers can get this very wide distribution to a large audience of readers.

Wikipedia is kind of extreme, where a very, very small group of people contribute pretty much everything.

We want Quora to last forever, and in order to last forever, it's going to need to have revenue. One of the best things about ads is that you don't need to exclude anyone.

In the past, there hasn't been much reliable information about startups and small businesses available online. It's information that's really valuable, and it's information that people want to share.

A lot of people really like to answer questions, and they really enjoy sharing their knowledge. Especially people who have valuable knowledge.

I have a view that if you build something that's good, and you keep making it better, it lasts.

Our goal is to build this up as a knowledge base that anyone can look at. We're not just interested in people answering their friends' one-off questions.

The Internet was supposed to allow anyone to set up a web page and share their knowledge with the world. But in practice, it's too difficult and takes too long, and almost no one does it.

Blogs are easy to start, but unless the author is famous, it takes years to build a following.

More than a billion people use the Internet, yet only a tiny fraction contribute their knowledge to it.

When you look at Google, its job is to find you the perfect web page. There are a lot of cases when you want to know something and a list of websites isn't ideal.

When you look at Yahoo Answers, there can be a lot of garbage. But if you're careful about the rules and supporting good contributions, over time you can get better and better, like Wikipedia.

Questions and answers is a big space, and there are lots of possible systems that you can create for different goals.

The area we define as what Quora's good at is long-form text that's useful over time, and where you care about who wrote the text. Not that you need to be friends with them, just that they're someone trustworthy.

Most of the stuff that people look at on Quora today was not written in the last month. You write something really good, and maybe it's the definitive answer on the Internet for the next 10 years. Maybe it's only a year, but not like a tweet, where it's only relevant for a day or a week.

When we get people to log in, they end up using Quora a lot more, and we can provide a lot better experience for them. We can show them a personalized news feed; we can send them digest emails and do all this ranking to find some stuff they want to read.

You can go to Pinterest, and they'll get to know who your friends are, but they don't get to know very much about what you've done in the past. They're starting with little information about you, and they have to do this personalization.

If you imagine your friend is recommending you content on a topic they're an expert on, they can do a really good job of that. They know what you're interested in, they know your personality, they know if you have a scientific type of mind-set or not.

We need to build systems that can automatically figure out what's high quality and what's not, and encourage users to contribute high-quality content. There's a lot of technical challenges in that.

In 2007 I was at Facebook, and we looked at some of the social networks in Asia, and they were full of games.

Focus on the long term, and always do what's right to grow the company and not make short-term decisions. And outlast everyone one.