Open files: tension, 7th rank and their positional motifs

From long ago, it began to develop and to discover different positional and tactical motives in chess: one is the exhaustive study of endgames, the other may be the study of tricks in full aperture, but what concerns us today is to learn about a concept that may be hard to understand and maintain by initiated players and intermediates: open files and its great importance in the middle and end of game. 

Authors and world champions like Capablanca or Botvinnik, wrote about the above-mentioned motif, giving it a fundamental importance even in the highest levels of the chess. 

Let's see an excelent game played by the legend M. Botvinnik: 

Tension, waiting and maintaining composure are the keys to master a file, as a way to more complex positional motifs, and to dominate if our opponent is neglected and starts a passive game. 

Browsing the forums of Chess.com, I found a very interesting game played by an average player, which can explain in greater depth our purposes:

It is very interesting how this user, despite his level, has managed to maintain his composure and master concepts, perhaps, a little deep for him. We recognize that his opponent has also helped him, but ItsOzzy's game was consistent and deserved the victory.

Let's put in practice what we learnt today with some interesting tactics: