[nawfalhasan]

Can someone briefly tell me what is the main USP/focus of this OS?

[shakna]

Windows compatibility.

It reuses a lot of WINE's core, and so on. The intent is a FOSS OS which can run Windows drivers and applications.

[amaccuish]

It's an open-source NT kernel and Windows userland, relying on Wine primarily where it can for userland, and their own kernel implementation.

[godDLL]

I use it as a Windows compatible VM in VirtualBox for dev, testing and general Windowsy things