Windows 10 Anniversary Update being rolled out to users

The Windows 10 Anniversary Update - the largest update to the PC software since it launched last year - will start to become available to consumers today.

More than 350 million devices have been upgraded to Windows 10 since the software was released last year.

The new update sees Microsoft's virtual assistant Cortana become more central, being used as part of any search, while a new feature called Windows Ink enables users to annotate on their screens more freely, and across different apps, with a stylus.

The Microsoft Edge web browser, introduced in Windows 10 to replace Internet Explorer, is also being tweaked so it becomes more power efficient.

The technology firm said: "We are committed to delivering continuous innovation to you: including features that bring Windows Ink and Cortana to the mainstream; a faster, more accessible and more power-efficient Microsoft Edge browser; advanced security features for consumers and enterprises; new gaming experiences and new tools for the modern classroom.

"Everyone running Windows 10 will get these new features for free."

The advanced security features include facial recognition technology, Windows Hello, being made available to log in to websites and apps.

The Anniversary Update comes days after Microsoft ended a free upgrade program for users eligible to update to Windows 10, which was released in July last year. Now, anyone wanting to move to the software from either Windows 7 or 8 must pay for Windows 10, with prices starting at £99.99 in the UK.