The long-awaited Windows 10 Anniversary Update, codenamed Redstone, is now available to download for all users.

Windows 10 users won't automatically get the update, though, as the firm is staggering the release over the next few days, or even weeks.

The update has been timed to coincide with the end of the free upgrade offer for Windows 7 and 8.1 users, which expired on Saturday.

This is the fruition of Microsoft's promise to make the operating system 'Windows-as-a-service', with free updates and upgraded features replacing new editions and service packs.

Microsoft said in a 'our users tell us' statement: "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."

People on the Windows Insider programme were able to try these extra features during beta testing, but they are now unleashed for the masses, including the fact that you cannot turn Cortana off.

Windows Hello will bolster security with biometric options, while Windows Ink will allow you to draw directly onto the screen without ruining your monitor.

Microsoft Edge, the little browser nobody loved, gets some efficiency improvements which will make it slightly less unappealing.

The free offer is officially over, but it was confirmed yesterday that anyone using Microsoft's accessibility features can in fact still get it free.

The other option is to pay 189 for the pro-edition or 99 for the standard version.