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Main » 2011 » August » 04
In ancient times, there was no paper. People pressed letters into clay tablets, or wrote with ink on papyrus, made from the stem of a plant that grew in Egypt, and on parchment, made from the skin of animals. The Chinese wrote on pages made of wood or silk. Then in the year 105, a man named Ts’ai Lun, who was a counselor to the Chinese emperor, found a way to make a writing material out of bamboo and other plants, along with fish nets and rags. This was the material we now call paper. Paper was much easier and cheaper to make than any other writing material known, and Ts’ai Lun became rich because of his invention. But later, he angered the emperor and was forced to drink poison. The Chinese guarded the secret of paper- making for many centuries. Then in 751, a Chinese army attacked Arabs in Central Asia. The Arabs won the battle and captured some Chinese soldiers who knew the secret of making paper. The Arabs later brought paper to Spain, and eventually it found its way to all parts of Europe. But though it was invented about a thousand years earlier, paper did not become common in Europe until the 12th century. The oldest piece of European paper that survives today comes from the year 1102. It wasn’t until the 19th century that paper makers found a way to make paper out of wood pulp. Today, most paper is made from wood, and only the best kinds of paper contain cotton or linen rags. More than 280 billion pounds of paper are produced around the world each year!
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QuestionHow do I create a Windows shortcut key? AnswerCreate a shortcut - Open the folder or directory that contains the program you wish to create a shortcut for.
- Right-click on the program and click Create Shortcut.
- This will create a shortcut named "Shortcut to <your program>" in the directory you are in. If you wish to rename this shortcut, right-click the file and click rename.
- Once the above steps have been completed, you can copy or cut this shortcut and paste it anywhere to execute this program.
Assign shortcut key to that Windows shortcut Once the shortcut has been created to assign a shortcut key to that Windows shortcut follow the below steps. - Right-click the shortcut and click Properties.
- Click the Shortcut tab.
- Click in the Shortcut key box and press a letter. For example, if you press "p" the shortcut key will automatically be made Ctrl + Alt + P. Which means if saved when pressing Ctrl and Alt and "P" all at the same time will run that shortcut.
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Using keyboard shortuts can greatly increase your productivity, reduce repetitive strain, and help keep you focused. For example, highlighting text with the keyboard and pressing Ctrl + C is much faster than taking your hand from the keyboard, highlighting the text using the mouse, clicking copy from the file menu, and then putting your hand back in place on the keyboard. Below are our top 10 keyboard shortcuts we recommend everyone memorize and use. Ctrl + C or Ctrl + Insert Copy the highlighted text or selected item. Ctrl + V or Shift + Insert Paste the text or object that's in the clipboard. Ctrl + Z and Ctrl + Y Undo any change. For example, if you cut text, pressing this will undo it. This can also often be pressed multiple times to undo multiple changes. Pressing Ctrl + Y would redo the undo. Ctrl + F Open the Find in any program. This includes your Internet browser to find text on the current page. Alt + Tab or Alt + Esc Quickly switch between open programs moving forward. Press Ctrl + Tab to switch between tabs in a program. Adding the Shift key to Alt + Tab or Ctrl + Tab will move backwards. For example, if you are pressing Alt + Tab and pass the program you want to switch to, press Alt + Shift + Tab to move backwards to that program. Windows Vista and 7 users can also press the Windows Key + Tab to switch through open programs in a full screenshot of the Window. Ctrl + Back space Pressing Ctrl + Backspace will delete a full word at a time instead of a single character. Ctrl + Left arrow / Right arrow Move the cursor one word at a time instead of one character at a time. If you wanted to highlight one word at a time you can hold down Ctrl + Shift and then press the left or right arrow key to move one word at a time in that direction while highlighting each word. Ctrl + Home / End Move the cursor to the beginning or end of a document. Ctrl + P Print the page being viewed. For example, the document in Microsoft Word or the web page in your Internet browser. Page Up / Space bar and Page Down Pressing either the page up or page down key will move that page one page at a time in that direction. When browsing the Internet pressing the space bar will also move the page down one page at a time. If you press Shift and the Space bar the page will go up a page at a time.
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QuestionWho invented the Internet? AnswerA single person did not create the Internet that we know and use today. Below is a listing of several different people who've helped contribute and develop the Internet. The idea The initial idea is credited as being Leonard Kleinrock's after he published his first paper entitled "Information Flow in Large Communication Nets" on May 31, 1961. In 1962 J.C.R. Licklider becomes the first Director of IPTO and gave his vision of a galactic network. In addition to the ideas from Licklider and Kleinrock, Robert Taylor helped create the idea of the network, which later became ARPANET. Initial creation The Internet as we know it today first started being developed in the late 1960's. In the summer of 1968, the Network Working Group (NWG) held its first meeting chaired by Elmer Shapiro with the Stanford Research Institute (SRI) with attendees: Steve Carr, Steve Crocker, Jeff Rulifson, and Ron Stoughton. In the meeting the group discussed solving issues related to getting hosts to communicate with each other. In December 1968, Elmer Shapiro with SRI released a report "A Study of Computer Network Design Parameters." Based on this work and earlier work done by Paul Baran, Thomas Marill and others; Lawrence Roberts and Barry Wessler helped to create the final version of the Interface Message Processor (IMP) specifications. Bolt Beranek and Newman, Inc. (BBN) was later awarded the contract to design and build the IMP sub network. Introduction of the Internet to the general public UCLA puts out a press release introducing the public to the Internet on July 3, 1969. First network equipment August 29, 1969 the first network switch and the first piece of network equipment called "IMP", which is short for (Interface Message Processor) is sent to UCLA. On September 2, 1969 the first data moves from UCLA host to the switch. The first distributed message and network crash On Friday October 29, 1969 at 10:30 p.m., the first Internet message was sent from computer science Professor Leonard KleinRock's laboratory at UCLA, after the second piece of network equipment was installed at SLI. This connection not only enabled the first transmission to be made, but is also considered to be the first Internet backbone. The first message to be distributed was "LO", which was an attempt at "LOGIN" by Charley S. Kline to log into the SLI computer from UCLA. However, the message was unable to be completed because the SLI system crashed. Shortly after the crash, the issue was resolved and he was able to log into the computer. E-mail is developed Ray Tomlinson introduces network e-mail in 1972. The first messaging system to send messages across a network to other users. TCP is developed Vinton Cerf and Robert Kahn design TCP during 1973 and later publish it with the help of Yogen Dalal and Carl Sunshine in December of 1974 in RFC 675. First commercial network A commercial version of ARPANET known as Telenet is introduced in 1974 and considered by many to be the first Internet Service Provider (ISP). Ethernet is conceived Bob Metcalfe develops Ethernet idea in 1973. TCP/IP is created In 1978 TCP splits into TCP/IP driven by Danny Cohen, David Reed, and John Shoch to support real-time traffic. This allows the creation of UDP. TCP/IP is later standardized into ARPANET in1983 and is still the primary protocol used for the Internet. DNS is introduced Paul Mockapetris and Jon Postel introduce DNS in 1984. HTML In 1990 Tim Berners-Lee develops HTML, which made a huge contribution to how we navigate and view the Internet today. WWW Tim Berners-Lee introduces WWW to the public on August 6, 1991. Internet experiences large growth In 1993 the Internet experienced one of its largest growths and today is accessible and used by people everywhere in the world.
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The answer to this question depends of your definition of a computer. The first known counting devices or tools were Tally Sticks from about 35,000 BC. The Abacus was then invented by the Babylonians in 2400 BC. In 1837, Charles Babbage, a British professor of mathematics described his idea for the Analytical Engine, the first stored-program mechanical computer. The Analytical Engine was designed to be powered by a steam engine and was to use Punched Cards, which was used to program mechanical looms at the time. What made the Analytical Engine unique was that it was designed to be programmed. It was because of this and the fact that it would be more than 100 years that any similar devices would be constructed, Charles Babbage, would be considered by many as the "father of computing”. Because of legal, financial, and political obstacles, the Analytical Machine would never be completed. Charles Babbage was also difficult to work with and alienated the supporters of his work. In 1939, John V. Atanasoff and Clifford Berry developed the Atanasoff-Berry Computer (ABC) at Iowa State University, which was regarded as the first electronic digital computer. The ABC was built by hand and the design used over 300 Vacuum Tubes and had capacitors fixed in a mechanically rotating drum for memory. The ENIAC (Electronic Numerical Integrator and Computer), constructed in the US in 1943, is widely regarded as the first functionally useful electronic general-purpose computer. Influenced by the ABC, it was a turning point in the history of computing and was used to perform ballistics trajectory calculations and used 160 kW of power. World War II is known to be the driving force of computing hardware development and one of such use of computers was in communications encryption and decryption. The UNIVAC I (Universal Automatic Computer) was the first commercially available, "mass produced” electronic computer manufactured by Remington Rand in the USA and was delivered to the US Census Bureau in June 1951. It used 5,200 vacuum tubes and consumed 125 kW of power. 46 machines were sold at more than $1 million each. The microprocessor eventually led to the development of the microcomputer, small, low-cost computers that individuals and small businesses could afford.
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— It's like a Brownie camera for the digital age: The microscopic device fits on the head of a pin, contains no lenses or moving parts, costs pennies to make -- and this Cornell-developed camera could revolutionize an array of science from surgery to robotics. The camera was invented in the lab of Alyosha Molnar, Cornell assistant professor of electrical and computer engineering, and developed by a group led by Patrick Gill, a postdoctoral associate. Their working prototype, detailed online in the journal Optics Letters (July 6, 2011), is 100th of a millimeter thick, and one-half millimeter on each side. The camera resolves images about 20 pixels across -- not portrait studio quality, but enough to shed light on previously hard-to-see things. "It's not going to be a camera with which people take family portraits, but there are a lot of applications out there that require just a little bit of dim vision," Gill said. In fact, Gill, whose other research interests involve making sense of how the brain's neurons fire under certain stimuli, began this invention as a side project related to work on developing lens-less implantable systems for imaging brain activity. This type of imaging system could be useful as part of an implantable probe for imaging neurons that have been modified to glow when they are active. Gill's camera is just a flat piece of doped silicon, which looks something like a tiny CD, with no parts that require off-chip manufacturing. As a result, it costs just a few cents to make and is incredibly small and light, as opposed to conventional small cameras on chips that cost a dollar or more and require bulky focusing optics. The scientists call their camera a Planar Fourier Capture Array (PFCA) because it uses the principles of the Fourier transform, which is a mathematical tool that allows multiple ways of capturing the same information. Each pixel in the PFCA reports one component of the Fourier transform of the image being detected by being sensitive to a unique blend of incident angles. While Fourier components themselves are sometimes directly useful, a bit of computation can also transform Fourier components into an image. The scientists will continue working to improve the camera's resolution and efficiency, but they think their concept can lead to a myriad of applications. It could be a component in any cheap electronic system -- in devices that, for example, detect the angle of the sun or a micro-robot that requires a simple visual system to navigate. Funding for this work was provided by the Defense Advanced Research Projects Agency and the National Institutes of
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