Waterproofing in the context of "IPhone"

A bivouac shelter or bivvy (alternately bivy, bivi, bivvi) is any of a variety of improvised camp site or shelter that is usually of a temporary nature, used especially by soldiers or people engaged in backpacking, bikepacking, scouting or mountain climbing. It may often refer to sleeping in the open with a bivouac sack, but it may also refer to a shelter constructed of natural materials like a structure of branches to form a frame, which is then covered with leaves, ferns and similar material for waterproofing and duff (leaf litter) for insulation. Modern bivouacs often involve the use of one- or two-person tents but may also be without tents or full cover. In modern mountaineering the nature of the bivouac shelter will depend on the level of preparedness, in particular whether existing camping and outdoor gear may be incorporated into the shelter.

Lanolin (from Latin lāna 'wool', and oleum 'oil'), also called wool fat, wool yolk, wool wax, sheep grease, sheep yolk, or wool grease, is a wax secreted by the sebaceous glands of wool-bearing animals. Lanolin used by humans comes from domestic sheep breeds that are raised specifically for their wool. Historically, many pharmacopoeias have referred to lanolin as wool fat (adeps lanae); however, as lanolin lacks glycerides (glycerol esters), it is not a true fat. Lanolin primarily consists of sterol esters instead. Lanolin's waterproofing property aids sheep in shedding water from their coats. Certain breeds of sheep produce large amounts of lanolin.

Lanolin in nature protects wool and skin from climate and the environment; it is also involved in skin (integumental) hygiene. Lanolin and its derivatives are used in the protection, treatment, and beautification of human skin.

Impervious surfaces are mainly artificial structures—such as pavements (roads, sidewalks, driveways and parking lots, as well as industrial areas such as airports, ports and logistics and distribution centres, all of which use considerable paved areas) that are covered by water-resistant materials such as asphalt, concrete, brick, stone—and rooftops. Soils compacted by urban development are also highly impervious.