The chili pepper is the fruit of the plants from the genus Capsicum, which are members of the nightshade family, Solanaceae. Chili peppers are considered fruit, not vegetables. Chili peppers are members of the nightshade (Solanaceae) family and are related to tomatoes, cherries and eggplant.
Chili peppers originated in South America, but are now grown around the world because they are used as spices or as medicine. Christopher Columbus reportedly sampled a chili pepper and thought it was a relative of the black pepper, dubbing it a "pepper", which is inaccurate, though the name persists today.
In South America, they were known as Aji.