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Cooper's Law
Martin Cooper (born December 26, 1928) is an American engineer. He is a pioneer in the wireless communications industry, especially in radio spectrum management, with eleven patents in the field.Encyclopedia of World Biography, 2008 encyclopedia.com On April 3, 1973, Cooper placed the first public call from a handheld portable cell phone while working at , from a Manhattan sidewalk to his counterpart at competitor . [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chicago
Chicago is the List of municipalities in Illinois, most populous city in the U.S. state of Illinois and in the Midwestern United States. With a population of 2,746,388, as of the 2020 United States census, 2020 census, it is the List of United States cities by population, third-most populous city in the United States after New York City and Los Angeles. As the county seat, seat of Cook County, Illinois, Cook County, the List of the most populous counties in the United States, second-most populous county in the U.S., Chicago is the center of the Chicago metropolitan area, often colloquially called "Chicagoland" and home to 9.6 million residents. Located on the shore of Lake Michigan, Chicago was incorporated as a city in 1837 near a Chicago Portage, portage between the Great Lakes and the Mississippi River, Mississippi River watershed. It grew rapidly in the mid-19th century. In 1871, the Great Chicago Fire destroyed several square miles and left more than 100,000 homeless, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Korean War
The Korean War (25 June 1950 – 27 July 1953) was an armed conflict on the Korean Peninsula fought between North Korea (Democratic People's Republic of Korea; DPRK) and South Korea (Republic of Korea; ROK) and their allies. North Korea was supported by China and the Soviet Union, while South Korea was supported by the United Nations Command (UNC) led by the United States. The conflict was one of the first major proxy wars of the Cold War. Fighting ended in 1953 with an armistice but no peace treaty, leading to the ongoing Korean conflict. After the end of World War II in 1945, Korea, which had been a Korea under Japanese rule, Japanese colony for 35 years, was Division of Korea, divided by the Soviet Union and the United States into two occupation zones at the 38th parallel north, 38th parallel, with plans for a future independent state. Due to political disagreements and influence from their backers, the zones formed their governments in 1948. North Korea was led by Kim Il S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phone Calls
A telephone call, phone call, voice call, or simply a call, is the effective use of a connection over a telephone network between the calling party and the called party. Telephone calls are the form of human communication that was first enabled by the development of the telephone and several inventions in the mid- to late-19th century. Initial technology involved point-to-point electrical wire connections between telephone installations, until centralized exchanges evolved where Switchboard operator, telephone operators established each interconnection manually at a telephone switchboard after asking the calling party for their call destination. After the invention of automatic telephone exchanges in the 1890s, the process became increasingly automated, eventually leading to the widespread adoption of digital exchanges in the second half of the 20th century, including the transition to wireless communication via mobile telephone networks and cellular networks. With the developm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
