History of Internet:• 1956: United States formed the Advanced Research Projects Agency (ARPA) within the Department of Defense, for the science and technology advancement in the military.• 1962: Paul Baran’s paper “ On Distributed Communications Networks” became the architectural ground work for ARPAnet.• 1967: The Association for Computing Machinery (ACM), Symposium on Operating Principles - - plan for nationwide network.• 1968: Network presentation to the ARPA.• 1969: ARPANET commissioned by the DoD for research into networking.• 1970: Norman Abramson, University of Hawaii, developed ALHOAnet. ARPANET begin using Network Control Protocol (NCP).• 1971: ARPANET expanded to 15 nodes (23 hosts).
The LaLonde report suggests that there are four general determinants of health including human biology, environment, lifestyle, and healthcare services. Thus, health is maintained and improved not only through the advancement and application of health science, but also through the efforts and intelligent lifestyle choices of the individual and society.
A major environmental factor is water quality, especially for the health of infants and children in developing countries.
Studies show that in developed countries, the lack of neighborhood recreational space that includes the natural environment leads to lower levels of neighborhood satisfaction and higher levels of obesity; therefore, lower overall well being. Therefore, the positive psychological benefits of natural space in urban neighborhoods should be taken into account in public policy and land use.
Achieving and maintaining health is an ongoing process. Effective strategies for staying healthy and improving one's health include the following elements:
Personal health depends partially on one's active, passive, and assisted observations about their health in their everyday life. The information gleaned from such observations may be used to inform personal decisions and actions (e.g., "I feel tired in the morning so I am going to try sleeping on a different pillow"), as well as clinical decisions and treatment plans (e.g., a patient who notices his or her shoes are tighter than usual may be having exacerbation of left-sided heart failure, and may require diuretic medication to reduce fluid overload) for patients who share their observations with their health care providers.
Personal health depends partially on the social structure of one's life. The maintenance of strong social relationships is linked to good health conditions, longevity, productivity, and a positive attitude. This is due to the fact that positive social interaction as viewed by the participant increases many chemical levels in the brain which are linked to personality and intelligence traits.
Volunteering also can lead to a healthy life. To be a volunteer, while gaining plenty of social benefits, people also take their mind off their own troubles. Volunteering could even add years of life. According to a university study, compared with people who did not volunteer, senior citizens who volunteered showed a 67% reduced risk of dying during a seven-year period.
Hygiene is the practice of keeping the body clean to prevent infection and illness, and the avoidance of contact with infectious agents. Hygiene practices include bathing, brushing and flossing teeth, washing hands especially before eating, washing food before it is eaten, cleaning food preparation utensils and surfaces before and after preparing meals, and many others. This may help prevent infection and illness. By cleaning the body, dead skin cells are washed away with the germs, reducing their chance of entering the body.