Explain the importance of the flying buttress in architecture

What will be an ideal response?

As the Gothic cathedral became the focal point for an entire town, its architecture represented a clear break with the Classical past. Unlike the Classical temple, which seemed to hug the earth, the Gothic cathedral soared heavenward. It rejected the static, rationalized purity of the Classical canon in favor of a dynamic system of thrusts and counter-thrusts; and it infused form with symbolic meaning. The soaring, vaulted ceiling were made possible by the flying buttress.
Rather than rounded arches, Gothic cathedrals used an ingenious combination of rib vault and pointed arches. Whereas the rounded vaults of the Romanesque church demanded extensive lateral buttressing, the steeply pointed arches of the Gothic period, which directed weight downward, required only the combination of slender vertical piers and thin lateral ("flying") buttresses. Instead of the heavy stone masonry, these cathedrals could feature areas of beautiful stained glass windows on the walls, adding to the lighter and airy interior space.