Elder is a smallish tree which is better known for its flowers and its berries than its timber. In previous centuries it had importance in medicine.
Uses of the flowers and berries include making country wines, jams and jellies. An extract of ripe elderberries is anti-viral so is good for colds.
Uses of the timber: elder doesn't get very big, and the timber is somewhat prone to splitting and warping. However if a good straight piece can be found and it is properly seasoned, it is a close-grained hardwood of attractive appearance.
Thin stems of elder are hollow, and have been used to make musical instruments: flutes, penny whistles, etc.