Pure Air Go Electric Scooter 2nd Gen – Waterproof & with Puncture Protection Fluid | Pure Electric

In physics, a fluid is a liquid, gas, or other material that may continuously move and deform (flow) under an applied shear stress, or external force. They have zero shear modulus, or, in simpler terms, are substances which cannot resist any shear force applied to them.

Although the term fluid generally includes both the liquid and gas phases, its definition varies among branches of science. Definitions of solid vary as well, and depending on field, some substances can have both fluid and solid properties. Non-Newtonian fluids like Silly Putty appear to behave similar to a solid when a sudden force is applied. Substances with a very high viscosity such as pitch appear to behave like a solid (see pitch drop experiment) as well. In particle physics, the concept is extended to include fluidic matters other than liquids or gases. A fluid in medicine or biology refers to any liquid constituent of the body (body fluid), whereas "liquid" is not used in this sense. Sometimes liquids given for fluid replacement, either by drinking or by injection, are also called fluids (e.g. "drink plenty of fluids"). In hydraulics, fluid is a term which refers to liquids with certain properties, and is broader than (hydraulic) oils.

Gen is most commonly seen as a contraction (such as Gen.) and it may refer to:

• Book of Genesis
• General officer
• Generation#Western world as in GenX, GenZ, etc.
• Genitive case

Gen may also refer to:

• Gen (film), 2006 Turkish horror film directed by Togan Gökbakar
• Gen (Street Fighter), a video game character from the Street Fighter series
• Gen Fu, a video game character from the Dead or Alive series
• Gen language, a language of Togo
• Gen-san, a character in the anime series Sky Girls
• Gen Asagiri (あさぎり ゲン (浅霧 幻)), a character in the anime and manga series Dr. Stone
• Gen Tomii (富井 彦, born 1973), Japanese Nordic combined skier
• Gen Hoshino (星野 源, born 1981), Japanese singer-songwriter, musician, actor, and writer
• Gen Kitchen, British politician
• Gen Shoji (昌子 源, born 1992), Japanese footballer
• Gen Urobuchi (虚淵 玄, born 1972), Japanese novelist, visual novel writer and anime screenwriter
• Gen Fukunaga (福永 元, born 1962), Japanese engineer and businessman
• Gen Nakatani (中谷 元, born 1957), Japanese politician
• Gen Horiuchi (堀内 元), Japanese ballet dancer and choreographer
• Gen Digital, a computer security software company in United States

GEN may refer to:

• GEN Corporation, of Japan
• GEN, Global Enterprise Network, a UK Internet Service Provider
• GEN Energija, a state-owned power company in Slovenia
• GEN, a website published by Medium
• Global Ecovillage Network
• Global Editors Network
• Gewestelijk ExpresNet, Dutch name for the Brussels Regional Express Network, a commuter rail service

Protection is any measure taken to guard a thing against damage caused by outside forces. Protection can be provided to physical objects, including organisms, to systems, and to intangible things like civil and political rights. Although the mechanisms for providing protection vary widely, the basic meaning of the term remains the same. This is illustrated by an explanation found in a manual on electrical wiring:

The meaning of the word protection, as used in the electrical industry, is no different to that in everyday use. People protect themselves against personal or financial loss by means of insurance and from injury or discomfort by the use of protective clothing. They further protect their property by the installation of security measures such as locks and/or alarm systems.

Some kind of protection is a characteristic of all life, as living things have evolved at least some protective mechanisms to counter damaging environmental phenomena, such as ultraviolet light. Biological membranes such as bark on trees and skin on animals offer protection from various threats, with skin playing a key role in protecting organisms against pathogens and excessive water loss. Additional structures like scales and hair offer further protection from the elements and from predators, with some animals having features such as spines or camouflage serving exclusively as anti-predator adaptations. Many animals supplement the protection afforded by their physiology by burrowing or otherwise adopting habitats or behaviors that insulate them from potential sources of harm. Humans originally began wearing clothing and building shelters in prehistoric times for protection from the elements. Both humans and animals are also often concerned with the protection of others, with adult animals being particularly inclined to seek to protect their young from elements of nature and from predators.

In the human sphere of activity, the concept of protection has been extended to nonliving objects, including technological systems such as computers, and to intangible things such as intellectual property, beliefs, and economic systems. Humans seek to protect locations of historical and cultural significance through historic preservation efforts, and are also concerned with protecting the environment from damage caused by human activity, and with protecting the Earth as a whole from potentially harmful objects from space.

Puncture, punctured or puncturing may refer to:

• a flat tyre in British English (US English "flat tire" or just "flat")
• a penetrating wound caused by pointy objects as nails or needles
• Lumbar puncture, also known as a spinal tap
• Puncture (band), an English punk band
• Puncture (film), a 2011 American film starring Chris Evans
• Puncture (topology), the removal of a finite set of points from a manifold
• Punctured neighbourhood, in general topology
• in coding theory, a punctured code, in which some of the bits of the data stream have been removed
• Pneumothorax, also known as punctured lung

With or WITH may refer to:

• With, a preposition in English
• Carl Johannes With (1877–1923), Danish doctor and arachnologist
• With (character), a character in D. N. Angel
• With (novel), a novel by Donald Harrington
• With (album), a 2014 album by TVXQ
• With (EP), a 2021 EP by Nam Woo-hyun