I have been using Linux for three years now and I only use Ubuntu-based OS. I am not an expert in computer engineering or whatever to say it.
These are my opinions why Ubuntu is so good comparing to other Linux distribution
Ubuntu is So Powerful
When you compare Ubuntu and Windows and you just use your laptop for common use; writing, browsing, and mulitmedia, they both are same. You will not face any serious problem.
Maybe it just that Microsoft Office's docx format that is not fully compatible with other word processor. But, it is not very important to be considered because today, people don't only use Microsoft Office, especially in Android. So, people will understand your problem and.
Ubuntu has Long Term Service (LTS)
Unlike many of Linux distributions, Ubuntu maintain longly its services in their LTS OS version. It usually be 5 years and can be extended 10 years for companies with extra costs.
Why LTS is important? Because if the servers, or developers anything to say, still support and maintain the OS, they will release update security, new apps, compatibilities, features, etc. So, they don't just put their OS to download then leave it be.
The latest version (Focal Fossa) has support till 2025.
Ubuntu is So Friendly
If you have little knowledge about Linux and computer science, you may think that using Linux is so hard but actually it is not when using Ubuntu-based distribution.
Ubuntu is very friendly especially the latest version. You don't need to know anything about computer science to use it normally. Ubuntu also come with a lot of language option so if you can't understand English, you can choose your own language.
Maybe you can use Ubuntu and forget about that you are using Linux.
Ubuntu is Ready to Use
Ubuntu comes with pre-installed with common aplication like LibreOffice, video player, etc. If you want more application, you just open the app store (which is snap in the latest Ubuntu). No need to search anything from the outside because everything is provided by default.
Just start to use and don't worry anything. Just do it!
Ubuntu is So Beautiful
Official Ubuntu Flavours (Official Ubuntu-Based Linux) comes with many variaties of Desktop Environment (DE) like Gnome, Plasma, Xfce, etc. Those DE have their own unique beauty so you can choose which is comfortable to you.
I recently use Kubuntu. It is an Ubuntu with Plasma DE. Love it.
Ubuntu is Linux
Yes this is the most important thing about Ubuntu. As a part of Linux families, Ubuntu has Linux's privilages. Ubuntu is free and open source software (FOSS). No worries about pirating because all is free.
All in all, Ubuntu is Linux and it is FOSS. Bravo!
Conclusion
If you are not familiar with Linux and want to use it no matter what is your intention, I recommend to use Ubuntu. If you don't like how Ubuntu's interface, I highly encourage to use the official Ubuntu flavours like Kubuntu, Xubuntu, Lubuntu, etc. If you still want more options, you can try other Ubuntu-based beyond the official flavours. Anyway, Ubuntu is just the best for me, you must try it.
Further Reading
https://sea.pcmag.com/apps/37485/ubuntu-2004-focal-fossa
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