The start-up’s valuation, which has nearly doubled in six months, shows continued enthusiasm for A.I. among investors.

The deal combined two of Mr. Musk’s companies, which have been on different trajectories. The transaction valued xAI at $80 billion and X at...

Companies like OpenAI and China’s DeepSeek offer chatbots designed to take their time with an answer. Here’s how they work.

With a national ban increasingly unlikely, let’s reflect on how the app both sparks joy among users and raises mental health concerns.

After the president made A.I. dominance a top priority, tech companies changed course from a meeker approach under the Biden administration.

That control is starting to fray as Mr. Johnson, a longevity guru known for performing experiments on his body, faces a backlash over the...

Steve Davis, a longtime Musk loyalist, is effectively the leader of the Department of Government Efficiency. Mr. Musk has likened him to chemotherapy.

The Snoo. The Nanit. The Hatch Rest. Many lists of baby gear mandate certain items, but our columnist wondered if it would be better...

The acquisition could make the Silicon Valley giant a bigger force in cybersecurity, and arrives months after an earlier round of talks collapsed.