If you want to take advantage of Microsoft’s free Windows 10 upgrade offer for Windows 7 and 8.1, time is running out. The offer will end on July 29.

Of course, there’s nothing particularly compelling about Windows 10. Unless you’re excited by the idea of seeing advertising in Windows. Or happy that (by default) Microsoft will track your Windows 10 activity.

Both Windows 7 and Windows 8.1 are still excellent operating systems. Windows 7 will be supported by Microsoft until January 14, 2020. Windows 8.1 will be supported until January 10, 2023. That means Microsoft will continue to develop (and make publicly available) security updates until 2020 for Windows 7 and 2023 for Windows 8.1.