HANGING PAWNS
Spassky was especially effective with hanging pawns.
A pair of pawns on adjacent files that are separated from all other pawns are known as "Hanging Pawns" (a term coined by Steinitz).
Hanging pawns possess strengths and weaknesses.
The elements of strength include the possibility of opening files through their advance and with this comes an increase in space, and the possibility of controlling key squares that can be used as outposts for Knights and Bishops.
On the other hand they can also be weak. They can only be defended by pieces. This vulnerability can be exploited by attacking them with pieces, forcing the opponent to protect them with pieces. The defending pieces can then be attacked and exchanged at a suitable moment and this can often result in the win of a pawn or forcing another pawn weakness elsewhere. They can also be weakened by forcing the advance of one of them leaving the other one backward and a hole into which a piece can be placed. A third way of exploiting their weakness is to attack them with a pawn of your own, this can force a pawn exchange that results in an isolated pawn.
The current view is that hanging pawns are weak if their side is behind in development but strong if their side is ahead in development.
Oh yeah u are right but it's a diagram to just identify hanging pawns
There are no hanging pawns in that diagram.
A pair of pawns on adjacent files that are separated from all other pawns are known as "Hanging Pawns" (a term coined by Steinitz).
FWIW here's a typical structure. The basic strategic discussion is similar to the IQP. The pawns give space and hopefully active pieces vs they're also a static weakness, which is typically more pronounced after they're not abreast.
The middlegames aren't winning, but the side with the hanging pawns typically has pressure. The endgames aren't losing, but the side with hanging pawns is typically under pressure.
By the way, wikipedia shows this exact structure and gives some general comments.
https://en.wikipedia.org/wiki/Pawn_structure