What can use RAM?

Question

Windows

Task Manager shows RAM usage of 5.9 out of 7.9 GB on the laptop. But at the same time, on another tab, I see that my current user, who is also the administrator and the only one, uses only 2.5GB. What else uses five? And how to optimize?
UPD.
If you sum up the values ​​in the working set column in the Resource Monitor, it will be 4.3GB, and at the bottom it will write next to the graph that 6.4GB is used at the moment ...

Answer 1

It depends on what you mean by memory usage.
A small part of the memory is occupied by the system.
A decent part of the memory is occupied by programs launched by the user.
The rest of the memory is used by the system for cache.
There is also usually a small amount of unused memory left, although if the memory is low this is rare.
Attach a screenshot of the memory tab from the resource monitor, it will be clearer.

Answer 2

Run the resource monitor, it will show everything in more detail.

Answer 3

Um ... Have you tried going to the task manager on the processes tab? There is also information "who, what and where" ...