Daddy longlegs is a popular name in North America for a harmless, long-legged creature related to the spider. Its legs are bent and its body hangs close to the ground. It is not an insect, but an arachnid. Another name for it is harvestman.
Daddy longlegs prey on small insects. They also eat dead insects and fallen fruit. When disturbed, many species of daddy longlegs can give off a bad odor, but they do not bite. Daddy longlegs are related to spiders, but they do not have fangs or spin webs. In the tropics, some species gather in great enough numbers to cover a small bush. If disturbed, all the daddy longlegs will shake violently, causing the entire bush to move.
In England, the crane fly is called daddy longlegs. The crane fly is an insect that has wings and looks much like a large mosquito, but it does not bite. Cellar spiders are sometimes called daddy-longleg spiders, but these creatures are spiders rather than daddy longlegs.