Compare and contrast the pysical descriptions of David and Goliath

From the text:

"...... he (Goliath) wore an elaborate tunic made up of hundreds of overlapping bronze fishlike scales. It covered his arms and reached to
his knees and probably weighed more than a hundred pounds. He had bronze shin guards protecting his legs, with attached bronze plates covering his feet. He wore a heavy metal helmet. He had three separate weapons, all optimized for close combat. He held a thrusting javelin made entirely of bronze, which was capable of penetrating a shield or even armor. He had a sword on his hip. And as
his primary option, he carried a special kind of short-range spear with a metal shaft as “thick as a weaver’s beam.” It had a cord attached to it and an elaborate set of weights that allowed it to be released with extraordinary force and accuracy. As the historian Moshe Garsiel writes, “To the Israelites, this extraordinary spear, with its heavy shaft plus long and heavy iron blade, when hurled by Goliath’s strong arm, seemed capable of piercing any bronze shield and bronze armor together.” Can you see why no Israelite would come forward to fight Goliath?

Then David appears. Saul tries to give him his own sword and armor so at least he’ll have a fighting chance. David refuses. “I cannot walk in these,” he says, “for I am unused to it.” Instead he reaches down and picks up five smooth stones, and puts them in his shoulder bag. Then he descends into the valley, carrying his shepherd’s staff. Goliath looks at the boy coming toward him and is
insulted. He was expecting to do battle with a seasoned warrior. Instead he sees a shepherd—a boy from one of the lowliest of all professions—who seems to want to use his shepherd’s staff as a cudgel against Goliath’s sword. “Am I a dog,” Goliath says, gesturing at the staff, “that you should come to me with sticks?”