The Technology Portal
Technology ("science of craft", from Greek τέχνη, techne, "art, skill, cunning of hand"; and -λογία, -logia) is the collection of techniques, skills, methods, and processes used in the production of goods or services or in the accomplishment of objectives, such as scientific investigation. Technology can be the knowledge of techniques, processes, and the like, or it can be embedded in machines to allow for operation without detailed knowledge of their workings. Systems (e. g. machines) applying technology by taking an input, changing it according to the system's use, and then producing an outcome are referred to as technology systems or technological systems.
The simplest form of technology is the development and use of basic tools. The prehistoric discovery of how to control fire and the later Neolithic Revolution increased the available sources of food, and the invention of the wheel helped humans to travel in and control their environment. Developments in historic times, including the printing press, the telephone, and the Internet, have lessened physical barriers to communication and allowed humans to interact freely on a global scale.
Technology has many effects. It has helped develop more advanced economies (including today's global economy) and has allowed the rise of a leisure class. Many technological processes produce unwanted by-products known as pollution and deplete natural resources to the detriment of Earth's environment. Innovations have always influenced the values of a society and raised new questions in the ethics of technology. Examples include the rise of the notion of efficiency in terms of human productivity, and the challenges of bioethics.
Philosophical debates have arisen over the use of technology, with disagreements over whether technology improves the human condition or worsens it. Neo-Luddism, anarcho-primitivism, and similar reactionary movements criticize the pervasiveness of technology, arguing that it harms the environment and alienates people; proponents of ideologies such as transhumanism and techno-progressivism view continued technological progress as beneficial to society and the human condition.
is the controlled addition of fluoride
to a public water supply
to reduce tooth decay
. Fluoridated water has fluoride at a level that is effective for preventing cavities; this can occur naturally or by adding fluoride. Fluoridated water operates on tooth surfaces: in the mouth it creates low levels of fluoride in saliva
, which reduces the rate at which tooth enamel
demineralizes and increases the rate at which it remineralizes in the early stages of cavities. Typically a fluoridated compound is added to drinking water, a process that in the U.S. costs an average of about $1.08 per person-year. Defluoridation is needed when the naturally occurring fluoride level exceeds recommended limits. A 1994 World Health Organization
expert committee suggested a level of fluoride from 0.5 to 1.0 mg/L (milligrams
), depending on climate. Dental cavities remain a major public health
concern in most industrialized countries
, affecting 60–90% of schoolchildren and the vast majority of adults, and costing society more to treat than any other disease. Water fluoridation prevents cavities in both children and adults, with studies estimating an 18–40% reduction in cavities when water fluoridation is used by children who already have access to toothpaste and other sources of fluoride. There is no clear evidence of adverse effects
other than dental fluorosis
. It is controversial, and opposition to it
has been based on ethical, legal, safety, and efficacy grounds.
In this month
- 3 May, 2000 – The outdoor recreation activity Geocaching (logo pictured), in which players use GPS to find hidden containers, is first played
Did you know...
was an astronomer
, and literary scholar
, and lived during the Eastern Han Dynasty
(AD 25–220) of China
. After beginning his career as a minor civil servant, he eventually became Chief Astronomer, Prefect of the Majors for Official Carriages, and then Palace Attendant at the imperial court. His uncompromising stances on certain historical and calendrical issues led to Zhang being considered a controversial figure, which prevented him from becoming an official court historian. Zhang applied his extensive knowledge of mechanics and gears in several of his inventions. He invented the world's first water-powered armillary sphere
, to represent astronomical observation; improved the inflow water clock
by adding another tank; and invented the world's first seismometer
, which discerned the cardinal direction
of an earthquake
500 km (310 mi) away. Furthermore, he improved previous Chinese calculations of the formula for pi
. His fu
(rhapsody) and shi
poetry were renowned and commented on by later Chinese writers. Zhang received many posthumous honors for his scholarship and ingenuity, and is considered a polymath
by some scholars.
- Parent project
- Related projects
Things you can do