Eric Schmidt is not Bill Gates. The cerebral computer scientist at the head of Google is far more affable than the intense, fiercely driven college drop-out who turned Microsoft into the world's most powerful technology company.

For the past two decades, Mr Schmidt, 54, has pursued a vision for computing very different from Mr Gates. In fact, his career has been defined almost in opposition to that of the Microsoft co-founder. This week, as Google disclosed that it would release a PC operating system to rival Microsoft's Windows, those two worlds collided.

If there is any personal animosity between the two men, it is not apparent. On Thursday, they met for lunch in the mountain air of Sun Valley, Idaho, at the annual retreat for media moguls and tech executives. Yet crossing swords with Mr Gates – and, often, losing – has had a deep effect on the Google CEO's competitive psyche. “His life experiences have certainly shaped him,” says Vic Gundotra, a former senior Windows developer who is now vice president of engineering at Google.