Microsoft says that WSL 2 uses virtualization technology to run the Linux kernel within a lightweight utility virtual machine, but it won't be a traditional VM experience with limited resources and reduced integration.
Windows 10 version 2004 introduces a real Linux kernel for Windows Subsystem for Linux that will make full system call compatibility possible.
In Windows 10 version 2004, Microsoft has been testing new features for Windows Subsystem for Linux, which uses in-house built Linux kernel and full system call compatibility to run more Linux apps.
WSL version 1 (WSL1), though, used a Linux-compatible kernel that translates Linux system calls so they could communicate and work with the Windows NT kernel.
With its own Linux kernel support, WSL 2 has access to full system call compatibility and it offers a whole new set of apps that you can run inside the container.