Short answers, pulled from the story.
Laundry is the washing of clothing and other textiles, and more broadly their drying and ironing as well. The word can also refer to the clothing itself or to the place where the cleaning happens. It comes from Middle English lavendrye, from Old French lavanderie, from lavandier.
Laundry was first done in watercourses, where moving water carried away materials that caused stains and smells. Clothes were rubbed, twisted, or slapped against flat rocks such as a beetling-stone, then beaten with a wooden tool called a washing paddle, battling stick, bat, beetle, or club. In many European villages it was done communally in a wash-house, or lavoir.
Around 1900, one in four ethnic Chinese men in the United States worked in a laundry, often 10 to 16 hours a day, because discrimination, a lack of English-language skills, and a lack of capital shut them out of most desirable careers. By the start of the Great Depression, Chinese people in New York City ran an estimated 3,550 laundries. After a 1933 law sought to drive them out of the business, the Chinese Hand Laundry Alliance successfully challenged it.
Laundry work has traditionally been highly gendered, with the responsibility in most cultures falling to women, formerly called laundresses or washerwomen. In India it was traditionally done by men called dhobiwallahs, and from 1850 to 1910 Zulu men laundered Europeans' clothes in Natal. In the Philippines the work generally fell to women called labanderas.
The right to dry movement formed when citizens protested rules that forbid drying clothes outdoors. Many homeowners' associations and communities in the United States prohibit clotheslines or limit where and when they can be used. Florida is the only state to expressly guarantee a right to dry, while Utah and Hawaii have passed solar rights legislation.
Drying at a temperature of at least 60 degrees Celsius, or 140 degrees Fahrenheit, for thirty minutes kills many parasites, including house dust mites, bed bugs, and scabies mites and their eggs. Just over ten minutes kills the mites themselves. Simple washing kills dust mites, and three hours of direct sunlight kills their eggs.