Programs to reset user data after reboot or shutdown?

Question

Computer networks

Hello, I went to courses for a long time and remembered such a program, but I don’t remember its name! I describe this program - the first: we had a disk on the computer divided into two parts, on the first part the system was installed there, on the second part (there was allocated 50 giga on all computers) the data was saved, that is, we also worked on our "projects" saved on this disk (on the second part), but if we say we save our project on the desktop or elsewhere, then when you restart or turn off the computer, all activity is erased .... For example, I will change the wallpaper, then I will reboot and the wallpaper will be the same again which were originally.
PS: you can at least create a "nuclear war", when you reboot everything will be as it was originally! Please tell me the names of such programs :)

Answer 1

• Restore original system state on every boot
  
• Software for a computer club or cafe?
  
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