With our work at Kazaa, we began seeing growing broadband connections and more powerful computers and more streaming multimedia, and we saw that the traditional way of communicating by phone no longer made a lot of sense.

Another differentiator is that Skype is free and simple to set up, and it costs us virtually nothing for a new user to join the Skype network, which is why we can offer the service for free.

We have 2 million users in the U.S. and about 13 million worldwide in more than 200 countries.

In fact, we just surpassed our first 1 million simultaneous users online.

If you can use a Web browser, you can use Skype.

With our work at Kazaa, we began seeing growing broadband connections and more powerful computers and more streaming multimedia, and we saw that the traditional way of communicating by phone no longer made a lot of sense.

It is very similar to companies like Google and other internet companies. When you go and search on Google you don't pay for that. But sometimes you click on an advert and Google makes money on that.

Then people started using it more and more and it became the most downloaded software on the internet.

If you could utilize the resources of the end users' computers, you could do things much more efficiently.

Skype is easy enough to use so that people don't need to be tech savvy - a lot of users just want to communicate with their friends and family, and they find this is the easiest, cheapest way.

We have just started, and if you compare the number of people using Skype to the number using a telephone network around the world, we're still just starting.

Skype is for any individual who has a broadband Internet connection.

What we are doing is taking advantage of the broadband Internet to provide basically unlimited free calls to anyone at a higher voice quality than they can with the phone lines.

We also have a conference call feature where up to five people can talk on one Skype call.

When radio stations started playing music the record companies started suing radio stations. They thought now that people could listen to music for free, who would want to buy a record in a record shop? But I think we all agree that radio stations are good stuff.

They also can combine voice with instant messaging and online file sharing.

People need to access Skype wirelessly, no matter where they are, and what happens is that we'll be taking advantage of the rollout of Internet everywhere - WiFi and WiMax in particular.

And the VCR did the same thing: the movie industry thought nobody would ever watch movies any more.

The telephone is a 100-year-old technology. It's time for a change. Charging for phone calls is something you did last century.

Angry Birds is one of the fastest-growing online products I've seen, growing even faster than Skype, and the company has done a brilliant job of extending it across different platforms and merchandise.

As an entrepreneur, if you're the originator, you need to be faster than ever.

As an investor, what we're not looking for is 'oh this is a cool app,' it's 'is this something that can become a big business?' You need to find those that can become real businesses.

If you want to be an entrepreneur, it's not a job, it's a lifestyle. It defines you. Forget about vacations, about going home at 6 pm - last thing at night you'll send emails, first thing in the morning you'll read emails, and you'll wake up in the middle of the night. But it's hugely rewarding as you're fulfilling something for yourself.

It's extremely hard to build a company with a product that everyone loves, is free and has no business model, and then to innovate a business model. I did that with Kazaa, had half a billion downloads but that wasn't a sustainable business.

Surround yourself with smart, dedicated people - to build something isn't a one-man show. It's more important to have smart people who really believe in what you're doing than really experienced people who may not share your dream.

When we look at investing, we always think about 'how defensible is this, how likely is it that somebody is going to copy this.' E-commerce tends to be something easy to copy because it's execution.

When we started Skype, if you look at analyst reports, no one forecasted it as a big business. Also when Google started, it was not fashionable to be in search. It's not trying to do the obvious - that's the hard part.

Silicon Valley is the best place to start a tech company in so many ways.

Video is moving online in a big way. It's proven to be a challenging market for some companies that start out as a pure Internet company such as Joost.

Over and over again, financial experts and wonkish talking heads endeavor to explain these mysterious, 'toxic' financial instruments to us lay folk. Over and over, they ignobly fail, because we all know that no one understands credit default obligations and derivatives, except perhaps Mr. Buffett and the computers who created them.

I do not fear computers. I fear the lack of them.

There's my education in computers, right there; this is the whole thing, everything I took out of a book.

And my real enemy is not to hold the specimen sterile, but it's the lighting. The light is our real enemy. So we have to work with very very poor lighting. But we can increase the light with computers.

Nanotechnology will let us build computers that are incredibly powerful. We'll have more power in the volume of a sugar cube than exists in the entire world today.

Computers are like Old Testament gods; lots of rules and no mercy.

The big question society will have to answer is whether it wants computers thinking like humans.

Diaspora starts about a thousand years from now. Most of human civilisation has moved inside computers; essentially, a major branch of our descendants consists of conscious software.

I do two things. I design mobile computers and I study brains.

Well, we didn't have our original drummer on our last record. And most of that album was not played as a band in the studio. It was mostly the world of computers and overdubs. There was very few things played live or worked out as a band.

After a semester or so, my infatuation with computers burnt out as quickly as it had begun.

Learning can take place in the backyard if there is a human being there who cares about the child. Before learning computers, children should learn to read first. They should sit around the dinner table and hear what their parents have to say and think.

Computers rather frighten me, because I never did learn to type, so the whole thing seems extraordinarily complicated to me.

They were saying computers deal with numbers. This was absolutely nonsense. Computers deal with arbitrary information of any kind.

But I'm so slow on it because I find it terribly hard writing blind on computers. The computer speaks to me, but it's just so slow, I'm so terribly slow using it.

Why does everyone think the future is space helmets, silver foil, and talking like computers, like a bad episode of Star Trek?

Yeah, computers are going to take over the programming business because they have become so fast recently that they can solve the Halting Problem in five seconds flat.

You can involve yourself in electronics, computers, puzzles... there's a lot of creativity and brain working. There's a lot to model trains that people don't realize.

At our computer club, we talked about it being a revolution. Computers were going to belong to everyone, and give us power, and free us from the people who owned computers and all that stuff.

With our work at Kazaa, we began seeing growing broadband connections and more powerful computers and more streaming multimedia, and we saw that the traditional way of communicating by phone no longer made a lot of sense.