How does Android render the GUI?

Question

linux

On Linux, there are two main and several side ways to draw a GUI in a tty. Major: X and Wayland. Mir was developed by Canonical, but Ubuntu moved to Wayland.
But in Android there is neither X, much less Wayland. Running programs from Ubuntu, CentOS and Arch is problematic.
How does Android display the GUI?

Answer 1

Running programs from Ubuntu, CentOS and Arch is problematic.

Well, in general, yes, because. Android does not have permission to run applications at the kernel or root level (and Linux requires root to install applications), and all applications run from a special sandbox called a virtual machine.
It used to be dalvik, now Android Runtime (ART)

Answer 2

something different, here is an old post on this topic