Zucchini is a summer squash which can reach nearly a meter in length, but which is usually harvested at half that size or less. Along with certain other squashes and pumpkins, it belongs to the species Cucurbita pepo. Zucchini can be dark or light green. A related hybrid, the golden zucchini, is a deep yellow or orange color.

In a culinary context, zucchini is treated as a vegetable; it is usually cooked and presented as a savory dish or accompaniment.Botanically, however, zucchini is a fruit. Zucchini, like all squash, has its ancestry in the Americas. However, the varieties of squash typically called "zucchini" were developed in Italy, many generations after their introduction from the Americas.