Late 1950s - Early 1960s: Second Generation Computers An important change in the development of computers occurred in 1948 with the invention of the transistor. It replaced the large, unwieldy vacuum tube and as a result led to a shrinking in size of electronic machinery. The transistor was first applied to a computer in 1956. Combined with the advances in magnetic-core memory, the use of transistors resulted in computers that were smaller, faster, more reliable and more energy-efficient than their predecessors. Stretch by IBM and LARC by Sperry-Rand (1959) were the first large-scale machines to take advantage of the transistor technology (and also used assembly language instead of the difficult machine language). Both developed for atomic energy laboratories could handle enormous amounts of data, but still were costly and too powerful for the business sector's needs. Therefore only two LARC's were ever installed. Throughout the early 1960s there were a number of commercially successful computers (for example the IBM 1401) used in business, universities, and government and by 1965 most large firms routinely processed financial information by using computers. Decisive for the success of computers in business was the stored program concept and the development of sophisticated high-level programming languages like FORTRAN (Formular Translator), 1956, and COBOL (Common Business-Oriented Language), 1960, that gave them the flexibility to be cost effective and productive. The invention of second generation computers also marked the beginning of an entire branch, the software industry, and the birth of a wide range of new types of careers. |
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Fiber-optic cable networks Fiber-optic cable networks may become the dominant method for high-speed Internet connections. Since the first fiber-optic cable was laid across the Atlantic in 1988, the demand for faster Internet connections is growing, fuelled by the growing network traffic, partly due to increasing implementation of corporate networks spanning the globe and to the use of graphics-heavy contents on the World Wide Web. Fiber-optic cables have not much more in common with copper wires than the capacity to transmit information. As copper wires, they can be terrestrial and submarine connections, but they allow much higher transmission rates. Copper wires allow 32 telephone calls at the same time, but fiber-optic cable can carry 40,000 calls at the same time. A capacity, Alexander Graham Bell might have not envisioned when he transmitted the first words - "Mr. Watson, come here. I want you" - over a copper wire. Copper wires will not come out of use in the foreseeable future because of technologies as DSL that speed up access drastically. But with the technology to transmit signals at more than one wavelength on fiber-optic cables, there bandwidth is increasing, too. For technical information from the Encyclopaedia Britannica on telecommunication cables, click here. For technical information from the Encyclopaedia Britannica focusing on fiber-optic cables, click here. An entertaining report of the laying of the FLAG submarine cable, up to now the longest fiber-optic cable on earth, including detailed background information on the cable industry and its history, Neal Stephenson has written for Wired: Mother Earth Mother Board. Click here for reading. Susan Dumett has written a short history of undersea cables for Pretext magazine, Evolution of a Wired World. Click here for reading. A timeline history of submarine cables and a detailed list of seemingly all submarine cables of the world, operational, planned and out of service, can be found on the Web site of the International Cable Protection Committee. For maps of fiber-optic cable networks see the website of Kessler Marketing Intelligence, Inc. http://www.britannica.com/bcom/eb/article/4/0... http://www.britannica.com/bcom/eb/article/4/0... http://www.wired.com/wired/archive/4.12/ffgla... http://www.pretext.com/mar98/features/story3.... |
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