How to make sense of the information on the RAM tab in Mac OS X Yosemite?

Question

macOS

1. Recently became an os x Yosemite user. I've been a Windows user all my life. Now, by analogy, I try to open the system monitor and monitor the memory. What I see: 8 types of different memory, which I personally find it difficult to understand. Well, with Physical and Swap, everything is clear. What do all the other types mean? What should you pay attention to, which of them affects the overall performance of the system, and what do these numbers tell the end user?
2. Well, the following question: each process has a "Compressed Mem" column, which means compressed memory. How to understand this column?
3. My laptop has 8GB of RAM, and almost always after half an hour of laptop operation, I see that 7.9 GB is already written in the Memory Used column, while I do not use any resource-intensive applications, except for the browser. Does this mean the laptop is running out of RAM?
4. What does all sorts of programs that supposedly speed up the system by clearing unused memory (Memory Diag).
5. Is it worth it to constantly close unused programs, or will it be enough to close the program window itself by clicking on the cross?
6. I want to fully and deeply understand how the operating system works with memory. Is there a more detailed article? Thank you.