The best part about Easy OS, in my opinion, is while you CAN install it on an internal HDD/SDD, you don't have to, and if you don't, it completely de-couples the operating system and its whole associated environment (programs, settings, preferences, files, everything) from the PC and its internal HDD/SDD.
The importance and flexibility of this cannot be overstated. Until now, Linux distros could be run "live" with no persistence from a flash drive but only for testing purposes, then you had to install them to your internal HDD/SDD to use them "for real".
The problem was, installing an OS to an internal drive and then customizing it tied the OS and that environment to the PC, and also made it difficult to do dual-boot or triple-boot setups to run multiple OS environments on that machine.
Now? Get a bunch of $10 USB flash drives and install different Easy OS versions on each. Customize each to your heart's content. Add software, change preferences and settings, set up a dev environment, whatever, and the whole thing forever lives on that flash drive, and IS NOT associated with that PC!
You'd think running permanently from a self-contained bootable USB stick would be slow and would kill the drive with too many writes, but Barry used ingenious adaptive RAM-caching techniques and write-limiting, lifespan-extending techniques to overcome all that, and Easy OS runs lightning fast this way! A great side effect of this is that if you screw something up badly, simply shutdown and choose NOT to save your session... and it's like it never happened! Sessions are in RAM and aren't "real" (except for the /files/ directory) until you CHOOSE to commit them to the USB stick. This protects against big screwups, and if you do NOT save at the end of most of your usual working sessions (and save all your files in /files/ for persistence), and you periodically start special very brief sessions where you only update stuff (browser etc.) then shutdown and choose to save, and you keep all your usual work sessions NOT saved at shutdown, this TOTALLY PREVENTS build-up of "crud" and slowdown in the OS over time! This is a WONDERFUL capability, I can never go back!
Plug an Easy OS USB stick into another PC, it (generally) works! Your entire environment is now ready for you to use, on that PC. Then, plug it into another one, same deal... there's your whole environment ready to use, on any machine, with no linkage between the OS/environment and the machine itself! This gives incredible flexibility!
Upgrading used to be a risk. What if the update bricks my PC? Now, in addition to Easy's built-in rollback functionality, you can also just clone the USB drive to another one, then update one of them. If it goes horribly wrong, just reboot into the other, and you're back where you started.
Worried about your environment getting corrupted and not booting anymore? Clone the USB stick to another periodically. Solved forever!
Your PC's hardware dies? Plug your (or one of your several!) Easy OS USB sticks into some other PC, and you're back in operation, with the entire environment and all your files exactly as you left them and want them!
It's this "decoupling" that's the best feature. I have three PCs, and several Easy OS versions on different USB sticks (Buster, Kirkstone, Scarthgap, Daedalus) and I can plug any of them into any of the PCs at any time. I have multiple complete computing environments that are independent a particular PC!
This is FANTASTIC. I tried to achieve this with Puppy but for a number of reasons it's a lot less feasible than it is with Easy OS! Puppy Linux with its savefile and inability to run entirely in RAM and unplug the boot drive completely after boot and several other limitations didn't feel like a "real" Linux OS, but Easy OS does and is!.
The only problem left was the move away from Debian-based Buster and to OpenEmbedded-based Easys resulting in a tiny repository with almost no software in it. But now with appi, flappi and most importantly Daedalus once again giving us access to the enormous Debian/Devuan repos just like Buster had, Easy OS is perfect!
Night and day difference compared to all other Linuxes! I tell all my technical/Linux-aware friends about it, and several of them are using it now and they love it!
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