Tonight is the night, Windows fans. Starting around midnight Eastern on Wednesday, June 29, 2015 Windows 10 will start rolling out to Windows Insider members. And if you're part of the first wave upgrading to Windows 10, your PC may already be primed for the upgrade.

Some Windows Insiders are reporting that Microsoft is already sneaking the Windows 10 installer files into C:/$windows.~BT , according to The Verge. Don't try getting clever, though: If you try to jump the gun and install Windows 10 ahead of time it likely won't work since a few key files are still missing.

Nevertheless, if you're expecting to see an upgrade in the next 24 hours some of the files may already be on your hard drive. Microsoft will start delivering upgrades at midnight Eastern time on Wednesday morning, The Verge says.

The impact on you at home: Silently downloading updates to your machine is part of the new era for Windows. Microsoft hopes to keep its user base current with the latest feature updates and security patches by giving Windows 10 Home users almost no opportunity to delay or skip Windows updates. Instead, they will be automatically downloaded, and then installed when the machine isn't in use.

Many users already download and install updates automatically in Windows 7 and 8.1, but some prefer to update their machines manually. That option is now pretty much gone. The good news is users can control when the updates are installed by scheduling them now, and if there are any problems Microsoft offers utilities to help you block a nasty update that messes up your system.

A new era

Microsoft's move to Windows 10 is unlike any operating system upgrade in the company's history. For the next year, Windows 7 and 8.1 users will be able to upgrade to Windows 10 for free instead of paying an upgrade fee for the new software.

Windows 10 is a major improvement over Windows 8 and 8.1, which are now widely regarded as Vista-like failures. The traditional Start menu is back for Windows 10, modern UI apps now exist in their own Windows on the desktop, and new features like Cortana and Task View improve your overall experience.

If you are running Windows 7, 8, or 8.1 and haven't signed up for your copy of Windows 10, there's still loads of time. You won't get your upgrade tonight, but you will stake your place in line for later waves of Windows 10 rollouts.