Cultivated cucumbers are grown around the globe. They most likely originated in India, and from there they spread to all of the warm regions of the Old World. Cucumbers are also found in the wild.
From Wikipedia: “Cucumber (Cucumis sativus) is a widely cultivated plant in the gourd family, Cucurbitaceae. It is a creeping vine that bears cucumiform fruits that are used as vegetables. There are three main varieties of cucumber: slicing, pickling, and seedless. Within these varieties, several cultivars have been created. In North America, the term "wild cucumber" refers to plants in the genera Echinocystis and Marah, but these are not closely related. The cucumber is originally from South Asia, but now grows on most continents. Many different types of cucumber are traded on the global market.”
“The cucumber is a creeping vine that roots in the ground and grows up trellises or other supporting frames, wrapping around supports with thin, spiraling tendrils. The plant may also root in a soilless medium and will sprawl along the ground if it does not have supports. The vine has large leaves that form a canopy over the fruits. The fruit of typical cultivars of cucumber is roughly cylindrical, but elongated with tapered ends, and may be as large as 60 centimeters (24 in) long and 10 centimeters (3.9 in) in diameter. Botanically speaking, the cucumber is classified as a pepo, a type of botanical berry with a hard outer rind and no internal divisions. Much like tomato and squash, it is often perceived, prepared and eaten as a vegetable. Cucumber fruits are usually more than 90% water.”
“In general cultivation, cucumbers are classified into three main cultivar groups: "slicing", "pickling", and "burpless".
- Slicing Cucumbers: “Cucumbers grown to eat fresh are called slicing cucumbers. The main varieties of slicers mature on vines with large leaves that provide shading. They are mainly eaten in the unripe green form, since the ripe yellow form normally becomes bitter and sour. Slicers grown commercially for the North American market are generally longer, smoother, more uniform in color, and have a much tougher skin. Slicers in other countries are smaller and have a thinner, more delicate skin. Smaller slicing cucumbers can also be pickled. ...”
- Pickled cucumbers: “Compared to slicers, picklers tend to be shorter, thicker, less regularly shaped, and have bumpy skin with tiny white or black-dotted spines. They are never waxed. Color can vary from creamy yellow to pale or dark green. Pickling cucumbers are sometimes sold fresh as “Kirby” or “Liberty” cucumbers. Pickled cucumbers are soaked in brine or a combination of vinegar and brine, although not vinegar alone, often along with various spices. Pickled cucumbers are called "pickles" in the US or "gherkins" or "wallies" in the UK, ...”
- Burpless cucumbers: “Burpless cucumbersare sweeter and have a thinner skin than other varieties of cucumber, and are reputed to be easy to digest and to have a pleasant taste. They can grow as long as 2 feet (0.61 m). They are nearly seedless, and have a delicate skin.”
“In a 100 gram serving, raw cucumber (with peel) is 95% water, provides 16 calories and supplies low content of essential nutrients, as it is notable only for vitamin K at 16% of the Daily Value.”
“According to the Food and Agriculture Organization of the United Nations for cucumber and gherkin production in 2013, China produced 76% of the global output, followed by Turkey, Iran, Russia and Ukraine.”
Aroma and taste:
“Most people report a mild, almost watery or light melon aroma and flavor of cucumbers resulting from compounds called (E,Z)-nona-2,6-dienal, (Z)-2-nonenal and (E)-2-nonenal. The slightly bitter taste of cucumbers results from cucurbitacins.”