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Compose your own sentences with each English equivalent of the words given in exercise 23. Compare your variants with the sentences of your partner.
25. Match each word in A with the Russian equivalent in B:
26. Work in pairs and decide whether these statements are true or false:
1. When you first turn on a typical computer, it must run an initial programme that sets up the operating system.
2. Read-only memory is never used for this initial boot up operation.
3. When you turn off the computer, this read-only memory provides the instructions the computer uses to begin loading the operating system from the hard drive.
4. The transistors used in digital integrated circuits, including microprocessors, act primarily as electronically controlled switches.
5. A computer programme is also known as a digital integrated circuit.
6. The millions of transistors on a typical computer chip are able to perform extremely complicated tasks, as we see everyday in modern computers.
7. None of modern monitors have memory in them.
8. Many sophisticated monitors are equipped with digital controllers that are almost full-fledged computers themselves.
9. Notebook computer displays use liquid crystals, liquids that contain long chain or disk-shaped molecules.
27. Guided summary. Use the information from the text below to complete this paragraph. You are free to make any changes:
Early History of Computer (Part 2)
By 1822 the English mathematician Charles Babbage was proposing a steam driven calculating machine the size of a room, which he called the Difference Engine. This machine would be able to compute tables of numbers, such as logarithm tables. He obtained government funding for this project due to the importance of numeric tables in ocean navigation. By promoting their commercial and military navies, the British government had managed to become the earth’s greatest empire. But in that time frame the British government was publishing a seven volume set of navigation tables which came with a companion volume of corrections which showed that the set had over 1000 numerical errors.
It was hoped that Babbage’s machine could eliminate errors in these types of tables. But construction of Babbage’s Difference Engine proved exceedingly difficult and the project soon became the most expensive government funded project up to that point in English history. Ten years later the device was still nowhere near complete, acrimony abounded between all involved, and funding dried up. The device was never finished.
Babbage was not deterred, and by then was on to his next brainstorm, which he called the Analytic Engine. This device, large as a house and powered by 6 steam engines, would be more general purpose in nature because it would be programmable, thanks to the punched card technology of Jacquard. But it was Babbage who made an important intellectual leap regarding the punched cards. In the Jacquard loom, the presence or absence of each hole in the card physically allows a coloured thread to pass or stops that thread. Babbage saw that the pattern of holes could be used to represent an abstract idea such as a problem statement or the raw data required for that problem's solution. Babbage saw that there was no requirement that the problem matter itself physically pass through the holes.
Furthermore, Babbage realized that punched paper could be employed as a storage mechanism, holding computed numbers for future reference. Because of the connection to the Jacquard loom, Babbage called the two main parts of his Analytic Engine the «Store» and the «Mill», as both terms are used in the weaving industry. The Store was where numbers were held and the Mill was where they were «woven» into new results. In a modern computer these same parts are called the memory unit and the central processing unit (CPU). The Analytic Engine also had a key function that distinguishes computers from calculators: the conditional statement. A conditional statement allows a programme to achieve different results each time it is run. Based on the conditional statement, the path of the programme (that is, what statements are executed next) can be determined based upon a condition or situation that is detected at the very moment the programme is running.
Babbage befriended Ada Byron, the daughter of the famous poet Lord Byron. Though she was only 19, she was fascinated by Babbage's ideas and thru letters and meetings with Babbage she learned enough about the design of the Analytic Engine to begin fashioning programmes for the still unbuilt machine. While Babbage refused to publish his knowledge for another 30 years, Ada wrote a series of «Notes» wherein she detailed sequences of instructions she had prepared for the Analytic Engine. The Analytic Engine remained unbuilt (the British government refused to get involved with this one) but Ada earned her spot in history as the first computer programmer. Ada invented the subroutine and was the first to recognize the importance of looping. Babbage himself went on to invent the modern postal system, cowcatchers on trains, and the ophthalmoscope, which is still used today to treat the eye.
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