Investors are always biased to invest in things they themselves understand. So venture capitalists like Uber because they like driving in black town cars. They don't like Airbnb because they like staying in five-star hotels, not sleeping on people's couches.

Every time you write an email, it is in the public domain. There are all these ways where security is not as good as people believe.

Ideally, I want us to be working on things where if we're not working on them, they won't happen; companies where if we don't fund them they will not receive funding.

When I moved to Cleveland, defense research was laying the foundations for the Internet. The Apollo program was just about to put a man on the moon - and it was Neil Armstrong, from right here in Ohio. The future felt limitless. But today, our government is broken.

I did not want to write just another business book.

I think competition can make people stronger at whatever it is they're competing on. If we're competing in some athletic event for competitive swimmers, really intensely competing, it's likely that both of us will become better, but it's also quite possible we'll lose sight of what's truly valuable.

I suspect Obama did not know he was recording Angela Merkel's cell phones.

I do think there is this danger that our society has made its peace with decline. I'd like to jolt them out of their complacency a little bit.

I think people in Europe are generally pessimistic about the future. They have low expectations; they're not working hard to change things. When you're a slacker with a pessimistic view of the future, you're likely to meet those expectations.

I worked at a law firm in New York very briefly.

I'm very pro-science and pro-technology; I believe that these have been key drivers of progress in the world in the last centuries.

How to teach people to do what hasn't been done is a great riddle.

I think anything that requires real global breakthroughs requires a degree of intensity and sustained effort that cannot be done part time, so it's something you have to do around the clock, and that doesn't compute with our existing educational system.

Americans mythologize competition and credit it with saving us from socialist bread lines. Actually, capitalism and competition are opposites. Capitalism is premised on the accumulation of capital, but under perfect competition, all profits get competed away.

There's absolutely no bubble in technology.

People are worried about privacy, and its one of the reasons people are using a service like SnapChat.

Whenever I talk to people who founded a company, I often like to ask the prehistory questions 'When did you meet? How long have you been working before you started the company?' A bad answer is, 'We met at a networking event a week ago, and we started a company because we both want to be entrepreneurs.'

Don't bother starting the 10,000th restaurant in Manhattan. Find something to do that if you don't do it, it won't get done.

One of my first investments was $100,000 in a Web-based calendar startup - and I lost every dollar.

You have to have respect for money, but sometimes you get people who stop thinking about their career, and for them, it is just a case of saying, 'Look at me. I have a lot of money now, and I can do whatever I want.' I wouldn't do that.

I don't like running that much, and during the off-season, I have to do it, but if I can replace it with tennis, it is better.

We won back-to-back titles in 2005 and 2006, and it was a fantastic achievement, a fantastic feeling. Once you experience that, you want to have it again.

I believe that the Premier League is the best league in the world, and having played in the Premier League for such a long time, it is to my advantage, and I know what to expect.

I'm so focused on the game that I hardly understand what the people sing or shout or what they do.

Iker Casillas is one of those keepers who always seems to be at his best in the really difficult games when he has hardly got anything to do but reacts when needed in those emergency situations.

You have to be consistent in your work, consistent in your performances, because, if not, then you might not have as many games as you would like. Less games you play, then less chances to have a clean sheet.

I understood I had to be good at school so I could play football in my free time. Usually, by the time I came home from school, I already had all my things ready for the next day, so I could put my bag on the side and go straight out to play football with my friends!

It's always good to have the right call in the end.

It's always difficult to say if anyone is in the best form of their career.

Unfortunately, money is very important in this world we live in, but it is up to every individual to deal with it.

You win the way you have to.

I always like to do things the right way.

Football is a collective sport, but goalkeeping is an individual sport.

If you take the autobiographies of great sports people, they are almost always the same. They start with zero; they are always ambitious, know what they want to do in life, and have the confidence to do it.

I speak all my languages basically every day with the people in the dressing room, and it's a pleasure to be able to do so. On the pitch, if it's a group of players I'm trying to communicate with, then I use English because you need to make sure everyone understands what you are saying.

You can be the best manager in the world, but if the players don't trust you, it will never work.

Who is the best goalkeeper in the world? It's always hard to choose because there are so many great goalkeepers.

In big clubs, you always have competitions for places.

Obviously, every player wants to keep their spot in the starting line-up, and I'm the same.

True fans will appreciate what I've done and the legacy I've left.

There are some people who have left me negative messages, but they aren't true Chelsea fans.

With goal-line technology, there are plenty of results that could be changed.

Unfortunately, the manager is always the one who gets under pressure the most.

You need to defend as a team to defend well.

Sometimes, when you have a young team full of enthusiasm, they don't feel any pressure; they just play.

Obviously, you have the physicality and the way the game is played in the Premier League. The goalkeeper is not as protected as in Europe or different leagues.

I think it's very useful when you want to be the team who create. You need to create this superiority at the back when you build up using the goalkeepers.

Sometimes, if a striker is not scoring as many goals, they can still be in good form.

Every time you can score more goals you should try to do so.

You can't control games for 90 minutes; there will be moments where the opponents will show their quality.