Cauliflower is one of several vegetables cultivated from the species Brassica oleracea in the genus Brassica, which is in the Brassicaceae (or mustard) family.

An annual plant that reproduces by seed, the cauliflower head is composed of a (generally) white inflorescence meristem. Cauliflower heads resemble those in broccoli, which differs in having flower buds as the edible portion.

Typically, only the head is eaten; the edible white flesh is sometimes called "curd". The global production of cauliflower and broccoli in 2020 was over 25.5 million tons and worth 14.1 billion US dollars.