What is the correct way to install tar.bz2, and why tar.bz2 at all?

Question

linux

Moved not so long ago from the Debian branch, and now there are no familiar installers.
1. What is the correct way to install tar.bz2, and why tar.bz2 at all?
I have not done this yet, but I suppose that you need to:
1. unzip (for example, with the tar system program (understanding came from the name)))
2. move to a specific directory (such as /opt (from personal observation)))
3. make a link ( the link should be symbolic) (I'm not sure, that's why I'm writing this question) (clarify my doubts, who can)
2. Why do files have the *.tar.bz2 mask? I don't understand what bz2 is?
If tar indicates that the program should be opened with tar and not zip (let's say so), then what is bz2? What should bz2 tell me?
3. What would you recommend to read in order to fully understand the process of portraying software in systems?

Answer 1

1.1) expand tar xvjf filename.tar.bz2
1.2) install (deploy first) - most Linux software uses the following sequence
./configure
make
sudo make install
if it doesn't, readme most often lies at the root
1.3) depends on the program, see about readme
2) en.wikipedia.org/wiki/Tar
3) readme projects