Blackberry is an edible fruit produced by many species in the genus Rubus in the family Rosaceae, hybrids among these species within the subgenus Rubus, and hybrids between the subgenera Rubus and Idaeobatus. Some varieties of blackberry plants are thornless.
What distinguishes the blackberry from its raspberry relatives is whether or not the torus (receptacle or stem) “picks with” (i.e., stays with) the fruit. When one picks a blackberry fruit, the torus does stay with the fruit. With a raspberry, the torus remains on the plant, leaving a hollow core in the raspberry fruit.