Several species of citrus fruits are called limes (literally: small lemons).
From Wikipedia: “A lime (from French lime, from Arabic līma, from Persian līmū, "lemon") is a hybrid citrus fruit, which is typically round, lime green, 3–6 centimetres (1.2–2.4 in) in diameter, and containing acidic juice vesicles. There are several species of citrus trees whose fruits are called limes, including the Key lime (Citrus aurantifolia), Persian lime, kaffir lime, and desert lime. Limes are an excellent source of vitamin C, and are often used to accent the flavours of foods and beverages. They are grown year-round.”
“In 2013, the total world production of lemons and limes was 15.42 million tonnes, with India leading production of 2.52 million tonnes.”
“Raw limes are 88% water, 10% carbohydrates and less than 1% each of fat and protein (table). Only vitamin C content at 35% of the Daily Value (DV) per 100 g serving is significant for nutrition, with other nutrients present in low DV amounts.”
“Lime flesh and peel contain diverse phytochemicals, including polyphenols and terpenes, many of which are under basic research for their potential properties in humans.”
“Limes have higher contents of sugars and acids than do lemons.
Lime juice may be squeezed from fresh limes, or purchased in bottles in both unsweetened and sweetened varieties. Lime juice is used to make limeade, and as an ingredient (typically as sour mix) in many cocktails. ...
In cooking, lime is valued both for the acidity of its juice and the floral aroma of its zest. It is a common ingredient in authentic Mexican, Vietnamese and Thai dishes. It is also used for its pickling properties in ceviche. Some guacamole recipes call for lime juice. ...
Lime is an ingredient in several highball cocktails, often based on gin, such as gin and tonic, the gimlet and the Rickey. Freshly squeezed lime juice is also considered a key ingredient in margaritas, although sometimes lemon juice is substituted.
Lime extracts and lime essential oils are frequently used in perfumes, cleaning products, and aromatherapy.”
“When human skin is exposed to ultraviolet light after contact with lime peel or juice, a reaction known as phytophotodermatitis can occur, which can cause darkening of the skin, swelling or blistering. Bartenders handling limes and other citrus fruits when preparing cocktails may develop phytophotodermatitis due to the high concentration of furocoumarins and other phototoxic coumarins in limes. The main coumarin in limes is limettin which has manifold higher content in peels than in pulp. Persian limes have a higher content of coumarins and potentially greater phototoxicity than do Key limes.”
It is best to buy limes that have green peels because if they are yellow they have already lost some of their flavor.
Limes can be stored in the refrigerator for up to three weeks. Since they dry out quickly, it is best to keep them in a plastic bag.
Limes are smaller than lemons and contain about twice as much juice. If you roll them on a hard surface before juicing them, they will yield even more juice.