How is a pine needle different from a maple leaf?

They are needles, not leaves. ---An Answer-- Actually needles are leaves and they serve the same purpose. The only real difference in the two are their physical appearance and the the types of trees that produce them. Leafy tress are referred to as "Deciduous" and will lose their leave in the fall of the year when the weather turn cooler. Tress that produce needles are referred to as "Evergreen" trees and they will retain their needle like leaves year round.