Public provision for the economic security and social welfare of all individuals and their families, especially in the case of income losses due to unemployment, work injury, maternity, sickness, old age, and death. The term encompasses not only social insurance but also health and welfare services and various income maintenance programs designed to improve the recipient's welfare through public services. Some of the first organized cooperative efforts to provide for the economic security of individuals were instituted by workingmen's associations, mutual-benefit societies, and labour unions; social security was not widely established by law until the 19th and 20th centuries, with the first modern program appearing in Germany in 1883. Almost all developed nations now have social security programs that provide benefits or services through several major approaches such as social insurance and social assistance, a needs-based program that pays benefits only to the poor. Seealso Social Security Act; unemployment insurance; welfare; workers' compensation.
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In finance, written evidence of ownership conferring the right to receive property not currently in the holder's possession. The most common securities are stocks and bonds. Governments, companies, and financial institutions use securities to raise money. Stocks are securities issued in the form of equity ownership. Bonds are securities that take the form of debt. They constitute promises to pay a specified amount at a specified date and to pay interest at a specified rate in the interim. Most government securities are bonds that pay a fixed amount of interest per year; unlike commercial securities, their repayment is guaranteed. Both stocks and bonds are traded publicly on organized exchanges such as the New York Stock Exchange, the London Stock Exchange, and the Tokyo Stock Exchange. External forces such as international troubles, changes in government policies, and trends in foreign stock markets all have an effect on security prices. For individual stocks, the company's current and prospective financial performance play an important role, as do overall trends within its business sector. Seealso investment; saving.
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Division of the United Nations whose primary purpose is to maintain international peace and security. The Security Council originally consisted of five permanent members—China (represented by the government on Taiwan until 1971), France, the United Kingdom, the U.S., and the Soviet Union (succeeded in 1991 by Russia)—and six rotating members elected by the United Nations General Assembly for two-year terms. In 1965 the number of nonpermanent members was increased to 10. UN members agree to abide by the Security Council's resolutions when they join. The Security Council investigates disputes that threaten international peace and advises on how to resolve them. To prevent or halt aggression, it may impose diplomatic or economic sanctions or authorize the use of military force. Each of the permanent members holds veto power in decisions on substantive matters, such as the application of sanctions. Decisions on both substantive and procedural matters require nine affirmative votes, including the affirmative vote of all five permanent members (though in practice a permanent member may abstain without impairing the validity of a decision).
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U.S. agency that advises the president on domestic, foreign, and military policies related to national security. With the Central Intelligence Agency, it was established by the 1947 National Security Act. It provides the White House with a foreign-policy-making instrument independent of the State Department. It has four members—the president, vice president, and secretaries of state and defense—and its staff is headed by the national security adviser.
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U.S. intelligence agency responsible for cryptographic and communications intelligence and security. Established in 1952 by a presidential directive (not by law), it has operated largely without Congressional oversight. Its director has always been a general or an admiral. Its mission includes the protection and formulation of codes, ciphers, and other cryptology as well as the interception, analysis, and solution of coded transmissions. It conducts research into all forms of electronic transmission and operates listening posts around the world for the interception of signals. Though its budget and the number of its employees is secret, the NSA is acknowledged to be far larger than the Central Intelligence Agency, possessing financial resources that rival those of the world's largest companies.
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Security is the condition of being protected against danger, loss, and criminals. In the general sense, security is a concept similar to safety. The nuance between the two is an added emphasis on being protected from dangers that originate from outside. Individuals or actions that encroach upon the condition of protection are responsible for the breach of security.
The word "security" in general usage is synonymous with "safety," but as a technical term "security" means that something not only is secure but that it has been secured. In telecommunications, the term security has the following meanings:
Security has to be compared and contrasted with other related concepts: Safety, continuity, reliability. The key difference between security and reliability is that security must take into account the actions of active malicious agents attempting to cause destruction.
It is very often true that people's perception of security is not directly related to actual security. For example, a fear of flying is much more common than a fear of driving; however, driving is generally a much more dangerous form of transport. The tool may be mistaken for the effect, for example when multiple computer security programs interfere with each other, the user assumes the computer is secure when actual security has vanished.
Another side of this is a phenomenon called security theatre where ineffective security measures such as screening of airline passengers based on static databases are introduced with little real increase in security or even, according to the critics of one such measure - Computer Assisted Passenger Prescreening System - with an actual decrease in real security.
Additionally, however, sometimes if it is perceived that there is security then there will be an increase in actual security, even if the perception of security is mistaken. Sometimes a sign may warn that video surveillance is covering an area, and even if there is no actual visual surveillance then some malicious agents will be deterred by the belief that there may be. Also, often when there is actual security present in an area, such as video surveillance, an alarm system in a home, or an anti-theft system in a car such as a LoJack, signs advertising this security will increase its effectiveness, protecting the value of the secured vehicle or area itself. Since some intruders will decide not to attempt to break into such areas or vehicles, there can actually be less damage to windows in addition to protection of valuable objects inside. Without such advertisement, a car-thief might, for example, approach a car, break the window, and then flee in response to an alarm being triggered. Either way, perhaps the car itself and the objects inside aren't stolen, but with perceived security even the windows of the car have a lower chance of being damaged, increasing the financial security of its owner(s). It is important, however, for signs advertising security not to give clues as to how to subvert that security, for example in the case where a home burglar might be more likely to break into a certain home if he or she is able to learn beforehand which company makes its security system. Types of securities
There is an immense literature on the analysis and categorisation of security. Part of the reason for this is that, in most security systems, the "weakest link in the chain" is the most important. The situation is asymmetric since the defender must cover all points of attack while the attacker need only identify a single weak point upon which to concentrate.
Aviation Security is a combination of measures and material and human resources intended to counter the unlawful interference with the aviation security.
Certain concepts recur throughout different fields of security.
See also the listing of experts at the Belfer Center for Science and International Affairs and in the national security entry.