• Microsoft's Copilot assistant has been rolling out on Windows 10 and Windows 11.
• Beginning later this month, device makers will release PCs with keyboards featuring a new Copilot key.
• It's the biggest change to the Windows keyboard in almost 30 years.

Microsoft on Thursday said keyboards on upcoming Windows PCs will feature a Copilot key for having text conversations with the software maker's virtual assistant. It's one of the most prominent additions to the Windows keyboard since the 1994 introduction of the Windows key for viewing the Start menu.

Copilot in Windows taps artificial intelligence models from Microsoft-backed startup OpenAI, which operates its own popular ChatGPT chatbot. It can compose human-like text in response to a few words of written input. People can tell it to write out emails, answer questions, create images and turn on PC features. Workers in businesses that pay for Copilot for Microsoft 365 can receive highlights of Teams chats and get help with writing Word documents.

Microsoft has started delivering Copilot on PCs with Windows 10, the world's most popular operating system, and Windows 11. People can hold down the Windows key and push the C key to summon the Copilot.

Now it's getting a dedicated key.

Although Windows isn't the juggernaut it used to be, Microsoft still derives about 10% of its revenue from the operating system, so anything it can do to spur a wave of PC upgrades could lead to a revenue bump. Companies such as Dell and HP are looking to sell replacements to the PCs that consumers, students and corporate workers bought during the Covid-19 pandemic. The technology industry has agreed on a term called the AI PC, which often means having special chip components inside devices to run computationally demanding models more efficiently than standard silicon.

Enhancements to Windows, PCs and at the chip level will make 2024 "the year of the AI PC," Yusuf Mehdi, Microsoft's head of Windows and Surface, wrote in a blog post.

Device makers will show off PCs with the Copilot key leading up to the CES conference in Las Vegas next week, ahead of availability starting later this month. The new key will appear on forthcoming Microsoft Surface PCs, Mehdi wrote.

In some cases, the Copilot key will replace the Menu key or the right Control key, a Microsoft spokesperson told CNBC in an email. Some larger computers will have enough room for both the Copilot key and the right Control key, the spokesperson said.

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