Ubuntu-based

"DistroX is a Ubuntu-based distro that provides a sleek desktop experience while being light on resources..."

"DistroY is a Ubuntu-based distro optimised for..."

"DistroZ is a Ubuntu-based distro designed to provide an easy transition for Windows users..."

I could go on. There are, in short, a lot of Ubuntu-based distros. Among my favourites are: 

• Linux Mint
• Linux Lite
• Pop! OS (which has taken a sabbatical to essentially rewrite Gnome in Rust)
• Zorin OS
• Tuxedo OS (for KDE)

All the above are Ubuntu-based, but are independent distros in their own right, as distinct from the official flavours of Ubuntu, like Kubuntu and Xubuntu.

There's a chap called Titus on Youtube, who gets quite sniffy about all this forking. He avers that you only need three distros. Those are:

• Debian
• Fedora
• Arch

He mentions Opensuse, which I would include, but dismisses it as too niche. He doesn't mention Slackware at all. He also rather charmlessly suggests you could eliminate 90% of "all these forks and Linux distributions and no-one would blink an eye.." Despite the smug, elitist tone, he does have a point, particularly when it comes to understanding why there are so many distributions. 

You and I could make our own distro. Let's call it John OS. So what do we want to base it on? Let's base it on Ubuntu in keeping with the title of the post (Ubuntu, itself, is based on Debian). So we take the Ubuntu base, and add an existing desktop -- say Cinnamon -- which we're going to customise to give it a unique look. Maybe move the bar to the top and set it to auto-hide, make it fatter or thinner, and install Plank at the bottom with our favourite selection of applications pinned. Let's go with Brave as the browser; Gnome Office (just to be different) as the office suite; Haruna as the media player. These choices will be described as "eccentric" if you're lucky enough to get reviews because there are more conventional choices: for example, Firefox is usually the first browser of choice. 

Distros come and go; there are lots of discontinued distros. Anyone remember Pinguy? But Titus's entirely valid point is that you could just have installed Debian or Ubuntu (to stick with the theme) and uninstalled and/or installed the things you needed to achieve the same effect. All the ingredients are out there; you can take the ingredients and bake the cake how you like. Distros are just ready made cakes in the patisserie window for you to choose from.