Jujube, in botanical lingo, Ziziphus jujuba. What a great name. And people thr0ughout greater Asia claim this plant, because other, more common names include China Date, Korean Date, and Indian Date. The “date” part comes from the size, shape, and texture of candied dry fruit, which remind people of Palm Dates.
Systematists search in vain for many truly close relatives that are edible, but this family is distantly related to the Roses, so the fruit could hang out with Apples and Rose Hips.
Opening one of the spongy fruit, you’ll encounter a ridged stone, inside which there will be seed. That qualifies Ziziphus fruit as a Drupe.