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

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.

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.

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.

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

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.

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.

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.

I think as more people use the phones to access the Internet, they have a lot less patience for trying to find things on the search engines. That is because you need to figure a lot of things out for search to work.

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