Cucumbers are unlikely to flow from your faucet anytime soon, but that's one of the few apparent differences between water and the cylindrical gourd. One of the world's most waterlogged fruits, cucumbers are 96 percent water.

But cucumbers also contain the sugars, minerals, amino acids and vitamins that human bodies crave after exertion. Researchers say a cucumber is twice as effective at hydrating as a glass of water, and, unlike commercial sports drinks, it's low in calories.

Here are seven facts to refresh your familiarity with the (usually) green-skinned fruit that's a staple of Greek salads and fresh salsas:

1. The vast majority of U.S. cucumbers are garden cucumbers, sometimes called regular cucumbers or common cucumbers. But cucumbers come in hundreds of varieties, including the stumpy, bumpy Kirby; the slender English cucumber and dark-green Japanese cucumber, both featuring inconspicuous seeds; the round lemon cucumber, which tastes sweet; and the flavor-packed Persian cucumber.

2. Cucumbers really ought to be stored in the refrigerator, even though it's tempting to keep them in a toolbox: Rubbing a slice of cucumber along a door hinge can reduce squeaking, while wiping down a bathroom mirror with a cucumber slice is supposed to keep the mirror from fogging up.

3. "Cool as a cucumber" isn't just a figure of speech: On a warm summer day, the inside of a cucumber is 20 degrees cooler than the surrounding air.

4. Before English speakers borrowed the word "cucumber" from Latin, the vegetable was known as an eorpaeppla, or earth apple.

5. Nutrient-rich cucumber skin is edible, but because conventional cucumbers are often coated with a synthetic wax to prevent bruising during shipping, it's always wise to scrub cucumbers clean before eating.

6. Roman Emperor Tiberius was so fond of cucumbers that his staff constructed greenhouses and raised beds to ensure a daily cucumber supply.

7. Cucumber sandwiches have been a British tradition since the Victorian age, when the elite discovered the fruit was perfectly suited to their low-energy lifestyles (it also played well in India, the cucumber's birthplace). London's The Guardian advised its readers on how to make a perfect cucumber sandwich, which begins by skinning the cucumber and slicing it thinly. Sprinkle the slices with salt and white pepper, then arrange them on slices of generously buttered soft white bread. Top off the sandwiches, trim the crusts and cut into triangles. Very classy.