The zucchini is a summer squash

Summer Squash

Summer squash are a subset of squashes that are harvested when immature . All summer squashes are the fruits of the species Cucurbita pepo , but they are considered vegetables in terms of culinary use...

 which often grows to nearly a meter in length, but which is usually harvested at half that size or less. It is a hybrid of the cucumber. Along with certain other squashes, it belongs to the species Cucurbita pepo

Cucurbita pepo

The species Cucurbita pepo is a cultivated plant of the genus Cucurbita. It includes varieties of squash, gourd, and pumpkin.*Acorn squash*Delicata squash*Dodi marrow, grown in South Asia*Gem squash*Heart of gold squash*Pattypan squash...

. Zucchini can be dark or light green. A related hybrid, the golden zucchini is a deep yellow or orange color.

In a culinary context, the zucchini is treated as a vegetable

Vegetable

The noun vegetable usually means an edible plant or part of a plant other than a sweet fruit or seed. This typically means the leaf, stem, or root of a plant....

, which means it is usually cooked and presented as a savory dish or accompaniment.