The small seeds, similar in size and appearance to cumin seeds, are used in Indian cooking (eg as an ingredient in garam masala) or a constituent of pan masala, where their digestive properties are exploited.
The leaves are finely divided and feathery, like dill. The herb is frequently used with fish.
Florence fennel, a cultivar of the plant, is grown for its bulb, which is used as a vegetable. As a vegetable, the stalks are used. A typical use would be stir-fry.