Microsoft Windows 10 will debut this summer.

Users operating Windows 7 or newer will be offered the upgrade to Windows 10 for free for one year. After that, Microsoft is not sure what to charge or if it should continue offering it for free, CNet reports.

Microsoft has a big goal for Windows 10; the company wants 1 billion devices to be powered by the operating system. The free upgrades is one way to get the masses to sign up in big numbers.

Joe Belfiore, vice president of operating systems, said Thursday the company really wants to get customers to upgrade as quickly as possible. After the first year, he does not know how customers will upgrade.

Microsoft has not confirmed it would stop offering a free upgrade to Windows 10 after the one-year time-frame expires.

Instead, the company has been focused on promoting the new operating system.

Belfiore said users who upgrade to Windows 10 will get "new features and benefits for a long, long time." He said add-ons included in Windows 10 will also include application and full OS updates.

Windows 10 is aiming to be the operating system that will run on any device with its universal apps. The operating system will adapt to the user, no matter what device they are on.

Microsoft's new strategy to offer customers with the free upgrade is different from how it has operated in the past. Normally, when a new Windows version was released, users wanting to upgrade had to purchase a CD or product key for a considerable cost.

Since there is no price on what Windows 10 will cost after one year, PC users will be encouraged to upgrade as soon as possible. Microsoft said Windows 10 will be a significant upgrade from the previous versions of Windows. The world's biggest PC-maker Lenovo says it will breathe life back into Microsoft's operating system, PCWorld reports.

For those who are looking at a preview of how Windows 10 will look, they should look to Windows Phones.

Windows 10 will be "pretty similar to the model you see with phones," according to Belfiore.