I've never personally liked celery or celeriac, even though I've used the herb frequently in professional cooking. It's just not something I would eat by personal choice.
Dried celery fruits
(often incorrectly named "celery seeds")
Celery has been cultivated in the Mediterranean region for at least 3,000 years. Cultivation spread to Central and Northern Europe as a consequence of the Capitulare de Villis of Charlemagne.
Leaves and root, both used as vegetable or spice. Celery fruits, often incorrectly termed "seeds", are a strong though rather uncommon spice.
Apiaceae (parsley family).
All plant parts are strongly aromatic. Compared with the wild form and the celery types used by the Romans, modern cultivars are significantly depleted in bitter constituents.
In Latin, the celery was called sedano, which gave rise to celery and its modern cognates in French, German, English and many other European languages and which was handed down directly into modern Italian. An alternative Latin name apium, is found in Spanish apio, Portuguese aipo, Catalan api and the regional German word eppich. The ultimate origin of both names is unknown but may share a common Indo-European root with the Sanskrit ap- "water". The species name graveolens means "strongly smelling" (Latin gravis "grave" or "heavy" and olens "smelling", from the verb olere).
Celery has been known in the Mediterranean region for millennia. Celery was considered a holy plant in the Greek classical period and Homer mentions them in his epics. Less known is that celery leaves were worn by the winners of the Nemean Games, similar to the use of bay leaves at the Olympic Games and laurel leaves at the Pythian Games.
The Romans valued celery more for cooking than for religion, but much superstition was connected with it. The plant was thought to bring bad fortune and was generally associated with death and the underworld.
Today, celery is a popular herb and vegetable in Europe. The leaves are sometimes chopped and used as a garnish (similar to parsley), but more frequently cooked in soups or sauces to improve the taste. For the latter purpose, the root (often combined with bay leaves or boldo leaves, parsley root and lovage) is suitable. Additionally, the cooked root can be eaten as a vegetable.
In England and the US, a variety of celery with fleshy stems is more popular than root celery (celeriac), the latter being more commonly used on the European continent although increasingly employed in fine dining restaurants. Celery also plays an important part in the Creole cookery of New Orleans, where celery stalks are used in dishes such as gumbo.
Celery fruits (sometimes incorrectly called "celery seeds") have a similar but much stronger aroma. They can be ground and mixed with salt to make dosage easier. The fruits are slightly bitter, which limits their usage, but they are a great addition to cooked vegetables. In North-Eastern India, the dried fruits of a related plant radhuni are used as a culinary spice, e.g. in the Bengali spice mixture panch phoron. In the West, celery fruits are sometimes found in commercial curry powder as a substitute for radhuni.