Corresponding Square concept in endgame

I still find it confusing, but it was helpful for me to realize that the theory of corresponding squares is a general concept and it covers many different types of situations, from very simple to extremely complex. So for example "the opposition" is one case of corresponding squares.

Dvoretsky puts it pretty simply: "Corresponding squares are squares of reciprocal zugzwang. We may speak of corresponding squares for kings, for king with pawns, and with other material, we may speak of correspondence between any pairs of pieces. The most commonly seen cases of corresponding squares are: the opposition, mined squares, and triangulation."

To start understanding more complicated situations I found it helpful to study this position:

Capablanca calls this 'the opposition,' you can get his book Chess Fundamentals free online.

The vernacular is a hundred years old, but the way they used it was "White has the opposition," meaning that white was the last one to move onto the corresponding square, forcing black to move away from it, which is usually a winning initiative.

What's the difference between this concept/theory and opposition tactic?

@Akbar2thegreat it is just two different views on the same topic. You can explain opposition with key squares. Sometimes opposition is more helpful for calculating long lines, sometimes one has to figure out manually the key squares.

@nhl_1
So, I more or less know it as I know opposition well.
But as I like exploring things, I would definitely read about it on Internet.

IMHO, anything 100 years old has gots to be mo better than the junk they's be makin today ...

In general, opposition applies to a subset of cases where key squares apply. In some positions, it is simplest to know the key squares, e.g. g8 and g7 are the key squares of a white h-pawn. Helps with calculating variations.