Couple of questions on Linux software

[MacBH928]

I have few questions about the Linux OS:

1-I was told that each Linux distro has its own "repository" which means its own pool of apps to download from. So what if a new version of software is released, I can't upgrade until the distro updates its "repository"? What if I want to use an older version? What if I want to use an app that has not been added to the "repository"?

2-I was told Linux does not have an "Applications" folder or "Programs". It install each piece of the app in different locations. If so how can I know which apps are installed? How can I uninstall it since it will definitely keep residue files?

3-Linux users refer to some stuff as "terminal tools". I am guessing these are just apps that run in the terminal. If I download and install them, how can I uninstall them and where do I look to see if its installed or not?

 

[DaveTheRave]

Ubuntu-based distributions use "PPA's" that you pull from to get software. You dont need to update Ubuntu itself to get updated software from PPA's. Sometimes PPA's can be considered unsafe if you don't trust the source.

Arch and Manjaro pull from an "Official Repository", which you can trust, and another one called "AUR (Arch User Repository)", which seems to be safe but is a step down from the Official Repository in terms of trustworthiness.

There are two big Linux software stores that are available to most if not all distributions, and they are safe places to get software:

Install Linux apps using the Snap Store | Snapcraft

Find and install the best Linux software for all major Linux distributions.

snapcraft.io

Flathub - Apps for Linux

Find and install hundreds of apps and games for Linux. Enjoy Firefox, Telegram, RetroArch, GIMP and many more!

flathub.org