Actually there are about 10 types of distros and hundreds of distributions for each. Last time I counted there are over 100 versions of downloadable linux. Ubuntu is controlled by MS which is Debian based, but there are dozens of Debian distributions including plain Debian. I use a minimalist Distro that boots in about 10 seconds and has nothing loaded in it like a Desktop environment but just a windows manager which is just about 10 virtual desktop screens but they are not desktops as per say like Windows, Mac, or Ubuntu has. Complex right? I do not even use a version of a file explorer, everything is terminal console based text and good old fashion commands. I do not even us Outlook when in Windows or any MS tools due t the spyware nature.