PWNLOGS

Note: You are ssh-ing from hostA to hostB in all the following cases except case 4. In case 4, you ssh from hostB to hostA.

Case 1

Case 2

Case 3

Case 4

Case 5

Courtesy:

Thanks to Paul Turner for the excellent explanations in his/her/their YouTube video.
Watch Paul Turner's youtube video on SSH port forwarding.