Hygiene

Cleanliness is the absence of dirt, including dust, stains and a bad smell. It can apply to humans, animals, clothing, eating utensils, plates, pans, cups, etc., food, other movable objects, floors, windows, walls, toilets, etc.

Purposes of cleanliness are health, beauty, absence of bad smell, other comfort, avoidance of shame, and for avoiding spreading dirt to people (or other body parts), places or objects. In the case of windows the purpose is also transparency.

Washing is often done with soap, detergent, etc., often a different kind for different applications.

People usually wash themselves. Little children and sick and disabled people may be washed by someone else. For fun lovers etc. may wash each other. Often a shower is used, and/or a bathtub. More frequent is washing of just the hands, e.g. before and after preparing food and eating, after using the toilet, after handling something dirty, etc.

Hygiene has also commercial and cultural aspects. TV advertising has been launching campaigns in many countries trying to imprint in public opinion minds that only clean and sterile is healthy and safe.

Hygienic practices -- such as hand washing, and the use of boiled (and thus sterilized) water in medical operations -- have a profound impact on reducing the spread of disease. This is because they kill disease-causing microbes (germs), or remove them from the immediate surroundings. For instance, washing one's hands after using the toilet and before handling food reduces the chance of spreading E. coli bacteria and hepatitis A, both of which are spread from fecal contamination of food.

However, certain practices such as the use of antibacterial soaps in the home are questioned. These soaps, which contain low concentrations of chemicals which kill bacteria, may when used intermittently lead common bacteria to evolve resistance to these chemicals. Similar to antibiotic resistance, this would make antibacterials far less useful when they are actually needed in medicine.

See also: dry cleaning, vacuum cleaner, washing machine.