In the past, when Microsoft developed new versions of Windows, it typically released technical previews near the end of the process, when Windows was nearly ready to ship. With Windows
10, new features will be delivered to the Windows Insider community as soon as possible " during the development cycle, through a process called flighting " so that organizations can see exactly what Microsoft is developing and start their testing as soon as possible.
Flighting is the process of running Windows Insider Preview Builds on your device. When you run these early versions of Windows and give us feedback, you can help us shape the future of Windows. Once you've registered for the program, you can run Insider Preview builds on as many devices as you want, each in the channel of your choice.
Reference:
https://docs.microsoft.com/en-us/windows/deployment/update/waas-overview#servicing-channels
https://docs.microsoft.com/en-us/windows/deployment/update/create-deployment-plan