The first volume of the tech baron turned philanthropist’s memoirs focuses on his parent’s struggles to control him – and a painful early loss

The enduring mystery about William Henry Gates III is this: how did a precocious and sometimes obnoxious kid evolve into a billionaire tech lord and then into an elder statesman and philanthropist? This book gives us only the first part of the story, tracing Gates’s evolution from birth in 1955 to the founding of Microsoft in 1975. For the next part of the story, we will just have to wait for the sequel.

In a way, the volume’s title describes it well. In the era before machine learning and AI, when computer programs were exclusively written by humans, the term “source code” meant something. It described computer programs that could be read – and understood, if you knew the programming language – enabling you to explain why the machine did what it did.

The AI startup has upended the industry by developing a model that costs much less to produce – and is available free to a universe of tinkerers

Nothing cheers up a tech columnist more than the sight of $600bn being wiped off the market cap of an overvalued tech giant in a single day. And yet last Monday that’s what happened to Nvidia, the leading maker of electronic picks and shovels for the AI gold rush. It was the biggest one-day slump for any company in history, and it was not alone – shares of companies in semiconductor, power and infrastructure industries exposed to AI collectively shed more than $1tn in value on the same day.

The proximate cause of this chaos was the news that a Chinese tech startup of whom few had hitherto heard had released DeepSeek R1, a powerful AI assistant that was much cheaper to train and operate than the dominant models of the US tech giants – and yet was comparable in competence to OpenAI’s o1 “reasoning” model. Just to illustrate the difference: R1 was said to have cost only $5.58m to build, which is small change compared with the billions that OpenAI and co have spent on their models; and R1 is about 15 times more efficient (in terms of resource use) than anything comparable made by Meta.