What is the weakest pawn when you start a game of chess? It is the KBP. Why? While all other pawns get the support from at least one of the pieces, KBP is the only pawn that has the King alone to defend it and you know that the King’s power is very limited in the early phases, itself being subject to attack by all and sundry in the opposition ranks! One idea of a quick castling on the King-side is to bring the support of the Rook for this pawn, besides putting the King in a safe position.
In fact, a lot many games have been decided by a successful attack on this pawn, often preceded by piece sacrifices! As a beginner, if you are not careful to watch out for opponent’s pieces targeting this pawn howsoever remotely, you may find yourself at the receiving end of a nasty surprise! Even Grandmasters have been known to fall victim to traps that exposed this weakness in their positions, with the game finished off in super-quick time!
In the article on some Exercises in assessing a chess game position, you have seen how attacks on the King targeted this position.