In mathematics, A and B have no fixed representation, but for a graph, A generally represents length and B generally represents width.

H is the abbreviation of English high, so H is generally used to represent the height of a figure or object.

S is the abbreviation of the English letter Square, so S is generally used to represent the area of a figure or object.

Extended data:

In mathematics, besides the representatives of A, B, H and S, there are also C, V, P, R and D..

C is the abbreviation of English letter circumference, so C is generally used to represent the circumference.

V is the abbreviation of the English letter volume, so V is generally used to represent the volume.

P is the abbreviation of English letter pressure, so P is generally used to represent air pressure.

R is the abbreviation of the English letter radius, so P is generally used to represent the radius.

D is the abbreviation of the English letter diameter, so D is generally used to represent the diameter.