Short answers, pulled from the story.
Lime is the fruit of several citrus species, most of which are hybrids within the genus Citrus, family Rutaceae. Commercial varieties include the Key lime (Citrus x aurantiifolia), Persian lime (Citrus x latifolia), and Makrut lime (Citrus hystrix), among others. Most are derived from crosses between citron, mandarin, pomelo, and micrantha.
During the 19th century, British sailors consumed limes and other citrus to prevent scurvy, a disease caused by vitamin C deficiency on long sea voyages. The practice was a closely guarded military secret and gave British sailors the nickname "limey".
A 100-gram serving of raw lime provides 35% of the daily recommended value of vitamin C. Lime juice also contains about 47 grams of citric acid per litre, roughly twice the concentration of grapefruit juice and five times that of orange juice.
Margarita photodermatitis is a phototoxic skin reaction caused by contact with lime juice or peel followed by exposure to ultraviolet light. The responsible compounds are furanocoumarins, including bergapten, limettin, psoralen, and xanthotoxin. Lime peel contains higher concentrations of these compounds than the pulp.
Limes originated in tropical Southeast Asia and South Asia. The Austronesian expansion, roughly 3000-1500 BCE, carried them to Micronesia and Polynesia. The spice trade brought them to the Middle East and Mediterranean by at least 1200 BCE.
World production of limes combined with lemons reached 23.6 million tonnes in 2023. India and Mexico led production that year.