This is probably something I don't understand since I am used to Windows and am only starting out with Ubuntu. I know that software in linux comes in packages what I don't understand is why can't non-admin users install software.

I mean, every application is run by a specific user, and that user will only be able to run that applciation with his privilages, so if he has no admin privileges, the application also won't be able to access unauthorized directories etc.

I want most of the time to work on my PC with a non-admin user since it seems more safe to me, most of the time I have no need for admin privileges. and even though I know viruses in linux are uncommon I still think the best practice is to work on the computer in a state that you yourself can't make any changes to important files, that way viruses also can't harm any important files, but I need to install software for programming and web-design etc. and first of all I don't want to switch users all the time. But also it sounds safer to me that everything being done on the PC will be done through the non-admin user.

I'll be glad to know what misunderstanding I have here, cause something here doesn't sound right.