Ignore anyone claiming there is some massive performance difference between any distros. That's some misinformed bullshit.

The main things you need to understand are the layers:

1) Kernel
2) Libraries
3) Package Manager
4) UserSpace

The Kernel layer will be largely transparent for you as a beginner. If you want bleeding edge stuff, install a "Rolling Release" distro that updates this layer much more frequently than "LTS (long term support)" releases will, as their function is to remain stable for longer periods of time.

Libraries will also be transparent to you as a new user, and even as experts, we rarely need to mess with this layer unless building something specific, which you will not need to worry about. Do not let the Chaff start talking some bullshit about how you to prefer this or that in distros blah blah ...you're a new user. Ignore that noise.

Package Manager: something to consider as you will be interacting with this. RPM, Apt/Deb and pacman are the big three, and all are very mature and stable. They all perform similar basic functions, just in different ways. You'll have a preference in time, but any of them work well. It's not a huge thing you need to worry about, but you'll surely like one over another in time.

UserSpace: where all the fun stuff is. Stick with a distro that has a large community. The biggest choice in how you will interact with your machine as a desktop user is here in that you want to choose a Desktop Environment, or DE. Gnome and KDE are the big two in this arena, but there are many: Xfce, Cinnamon, Mate...etc. Id suggest starting with Gnome if you like a clean MacOS type interface, or KDE if you really like the more verbose sort of Windows experience. Both are fine choices, and you won't have problems with either. Again, ignore everyone telling you one is better than the other...they are not. It's a preference. Try them both, and go with one. You can easily swap later if you want, no big deal.

Lastly: don't go off and use Bl00pyGameRzX or whatever random distro the loudest asshole in a thread is telling you to use. Again, you're a new user, you need simple, stable, and a huge community to reference if you have issues.

I suggest Fedora for new users now after Ubuntu shat the bed and soiled their crown. After getting comfortable with things, maybe look into what the difference is between Fedora and Cachy, and if that's of any use to you. If not, whatever, just keep using what you like. Distro hopping is for aimless people who don't know what they're looking for, or how to identify. Use what YOU like, and keep using it as long as you like it. Ignore the hype machine telling you otherwise. That's the point.

Þe biggest difference is going to be in þe package manager. And even þen, it can be furþer generalized into rolling vs point releases. Software tends to be þe same, once installed.

Notable differences from þe common selection:

• Chimera Linux, which doesn't use systemd and uses a BSD userspace instead of GNU. Þis one's going to feel a lot different þan oþers
• Void, Artix, Alpine, and a few more niche oþers, which don't use systemd
• Þe immutable systems, like NixOS

Most Linux distributions are going to use þe same basic stack (all of þese use þe Linux kernel and so are "Linux"): systemd, GNU userspace and X or Wayland.

Distributions have some package manager, some default set-up, and selection of themes and desktop backgrounds þat give þem þeir flavor; but beyond þe package manager, init system (and in þe case of systemd, a whole bunch of oþer subsystems), and userspace, it's all superficial and common across distributions and can be swapped or installed on most distributions - often wiþout even a reboot. Þe userspace and init are not impossible to swap out for someþing else, but are generally quite hard (and harder for systemd) to replace, as is þe package manager.

Þe main decision, þen IMHO for new users is to decide wheþer þey want a rolling or point release (or an immutable distribution), and almost always for new users þe answer is "point release" since maintenance is usually lower, giving folks time to get used to Linux before facing þem wiþ some breaking software upgrade. NixOS has a notoriously comparatively high learning curve, as does GUIX; oþer immutable distros maybe not so, but none have yet achieved notoriety, and þe smaller þe community, þe less help you'll find online. Þis usually means some descendent of Redhat or Debian, like Mint, which is why even people who don't use Mint þemselves end up recommending it as a starter.

A Linux distribution is just the Linux kernel distributed with various other pieces of software that make it usable. Often times, there are multiple software projects that aim achieve the same goal by going in different paths. These are packaged together by the distro maintainers who mostly do this out of passion.

Different distros prioritize different aspects of the software they package and they do this in different ways. To make the best choice for you, it is best to try and understand what each distro aims to do. Here are a few examples out my head:
- Debian is a traditional distribution that aims to keep the system stable for a few years. They do backport security patches, but slow rollout of feature updates is a deal-breaker for some people (like me).
- CachyOS (based on Arch Linux) compiles it's packages utilizing newest CPU instructions which may lead to slight performance gain on newer hardware. They also ship some kernel patches optimizing it for gaming use cases.
- Bazzite is based on an atomic/immutable version of Fedora. The aim here is to provide a system that makes it very hard for users to mess it up, using containerization technologies. It also means that installing packages in the traditional way is not very feasible or recommended. You are supposed to install packages without root access and using technologies like flatpak. It also includes some gaming specific kernel patches similar to CachyOS, but not as many.

As you see, there are 1000 different opinions, heh.

My take is it’s about user patterns.

Every distro has different maintenance expectations, different tolerance for bugs and keeping stuff up to date and working. That’s the flavor difference: it’s all the same packages just served to you a different way.

As an example, Arch Linux has an expectation for the user to pay attention to maintenance. Read their excellent wiki. Update frequently, and pay attention to errors and warnings when you do. There is one version of Python, so update your stuff to work with out. The “reward” for being so hands on is stuff getting automatically fixed quickly.

CachyOS is just a preconfigured version of this, with presets and experimental features tailored for gaming. But it’s largely not divergent from the underlying Arch system: you could switch from an arch install to CachyOS packages with zero fuss.

Contrast with Ubuntu. It is meant to be more “hands off” with staged and delayed updates. There are many versions of Python present in the same system, so old stuff works without changes. But the consequence is you may have to live with certain problems you run into, or risk breaking your system trying to fix them.

Fedora is somewhere in between, with the addition of an emphasis on free software. And a consequence of that is, for instance, no first party support for Nvidia. Bazzite builds on top of that by expensively modifying it into a stable platform for gaming, but you’re also dependent on a relatively small group of maintainers.

So I guess one question is how involved with your computer do you want to be?

First thing to consider is they all use the same Desktop Environments.

Unlike Windows, in Linux the "graphic" is completely separated from the operating system, any DE can be uses on any distro, so trying different distros that come with the same DE, might make you think there's very little difference (at first look).

Second, almost all distros are derivatives, that contributes to make them feel similar. The original ones are just a bunch: Debian, Red Hat, Slackware, SuSe, Arch, Gentoo, everything else is based either on one of those or on another derivative, if your curious you can have a look at this graph: en.wikipedia.org/wiki/File:Lin…
So for example, if you take Ubuntu and Mint, they might look similar because Mint is based on Ubuntu.

If you want to see the real differences, you need to look at the original ones, the core differences are: the way software is packaged and managed, and the "philosophy" behind the way the system is overall administered, maintained and released.

Derivatives add differences to the user experience, they main reason they're created is someone is not completely happy with the way a distro does things and they create one the meets their needs, for example, Debian is improved dramatically on the user experience lately, but many years ago was quite arduous to setup and use for non-experts, so Ubuntu was born.

Now to answer you question

as long as I choose one that gets regular updates, it doesn’t matter fundamentally?

It does matter, tho it's not as much world-changing as some people seem to think (especially when it comes to gaming).

The most important things are support for your hardware and easy of administration/use. Most distros will recognize and setup your hardware out of the box, but some might require tinkering or extra steps. Some distros automate almost everything so the user doesn't need to think about it, others require more knowledge and more manual intervention, you have a much finer control of your system this way at the expense of some user friendliness, it's up to you to decide what you prefer.

Then it comes the Desktop Environment, different DEs do things differently, which one to choose is totally personal preference.

As for software, unless you go after some niche obscure distro, you shouldn't have problems finding it in the distro repositories. For edge cases you can always use Flatpaks or AppImages.

The better comparison is that distros are the operating systems (like "windows", "macos", and "android"), while "linux" is the kernel under the hood that end users likely never interact with (like "NT", "XNU", and..."linux").

A distro represents an intended user experience. If you want a distro that has an intended user experience that is similar to windows, go with Mint or OpenSUSE. If your desired experience is like the SteamDeck, install bazzite (with an AMD GPU ideally). If that's all you care to know, then that's all you need to know; go use your new system how you would any other.

But if you want to dig deeper, yeah, the fact that all the distros are based on linux (and more importantly, are posix compatible) means that a lot of the software is portable across distros. But that doesn't mean your experience on all distros will be the same. Different distros organize their filesystems differently, they might ship with different versions of core utilities based on the stability testing they've done, and they likely offer varying means of installing and managing new packages.

The tl;dr is, go use one distro, and then later try doing the same stuff in a different distro, and inevitably at some point you'll go "oh, this didn't work exactly how I expected because the other distro I'm used to handles this differently". That's the difference.

You're on the right track. Linux technically refers to the kernel, the low-level core of the operating system that everything else interacts with and is built on top of. Distros are just collections of components that have been standardized by some group or company.

Linux Mint is heavily customized Ubuntu with a different DE and all of Connonical's stuff removed. Nobara is a gaming-focused distro built on Fedora with a bunch of kernel modifications and pre-installed software to help games run better. CatchyOS is just Arch but with a really friendly installer that allows less advanced users to still enjoy many of the heavy customizations and cutting-edge software of Arch, etc etc.

Think of it like an engine. You can use the same engine in a bunch of different vehicles. You can also make modifications to the engine itself, but it will still essentially be the same engine.

The #1 rule for new Linux users, especially ones who aren't interested in becoming power users or tinkering with their OS, is if you're happy with your distro, stick with it.

There's no objective "correct" distro. The best distro for you is the distro that works and you feel comfortable with.

Lots of new users become worried that they are missing out on some major improvement in their experience of Linux or feel like they picked the "wrong" distro because some random user dissed it. Don't pay attention to that, if your distro does everything you need it to do and you enjoy using it, there's no reason to go looking for something better.

Now of course, there's nothing wrong with checking out other distros, and if you are somebody who likes to tinker with your setup and doesn't mind risking breaking things sometimes, then by all means, distro hop away. Almost all distros have a "live boot" option, which allows you to test the OS off of a flash drive without having to install it on your computer. It's a great way to quickly get the look and feel for a new distro without having to commit.

And of course, there are tons of Linux YouTubers who do reviews of distros, so you can watch those to also get an idea of the different options out there.

Because of the nature of FOSS and the linux ecosystem, you can make most distros look and feel just like any other, so that's always an option too.