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| Words of Wisdom: | "Do not always try to do the right thing! There is NO right thing, as there is NO true mistake." - claire |
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Computers A common misconception about computers is that they are smarter than humans. Actually, the degree of a computerıs intelligence depends on the speed of its ignorance. Todayıs complex computers are not really intelligent at all. The intelligence is in the people who design them. Therefore, in order to understand the intelligence of computers, one must first look at the history of computers, the way computers handle information, and, finally, the methods of programming the machines. The predecessor to todayıs computers was nothing like the machines we use today. The first known computer was Charles Babbageıs Analytical Engine; designed in 1834. (Constable 9) It was a remarkable device for its time. In fact, the Analytical Engine required so much power and would have been so much more complex than the manufacturing methods of the time, it could never be built. No more than twenty years after Babbageıs death, Herman Hollerith designed an electromechanical machine that used punched cards to tabulate the 1890 U.S. Census. His tabulation machine was so successful, he formed IBM to supply them. (Constable 11) The computers of those times worked with gears and mechanical computation. Unlike todayıs chip computers, the first computers were non-programmable, electromechnical machines. No one would ever confuse the limited power of those early machines with the wonder of the human brain. An example was the ENIAC, or Electronic Numerical Integrator and Computer. It was a huge, room-sized machine, designed to calculate artillery firing tables for the military. (Constable 9) ENIAC was built with more than 19,000 vacuum tubes, nine times the amount ever used prior to this. The internal memory of ENIAC was a paltry twenty decimal numbers of ten digits each. (Constable 12) (Todayıs average home computer can hold roughly 20,480 times this amount.) Today, the chip-based computer easily packs the power of more than 10,000 ENIACs into a silicon chip the size of an infantıs fingertip. (Reid 64) The chip itself was invented by Jack Kilby and Robert Noyce in 1958, but their crude devices looked nothing like the sleek, paper-thin devices common now. (Reid 66) The first integrated circuit had but four transistors and was half an inch long and narrower than a toothpick. Chips found in todayıs PCs, such as the Motorola 68040, cram more than 1.2 million transistors onto a chip half an inch square. (Poole 136) The ENIAC was an extremely expensive, huge and complex machine, while PCs now are shoebox-sized gadgets costing but a few thousand dollars. Because of the incredible miniaturization that has taken place, and because of the seemingly ³magical² speed at which a computer accomplishes its tasks, many people look at the computer as a replacement for the human brain. Once again, though, the computer can only accomplish its amazing feats by breaking down every task into its simplest possible choices. Of course, the computer must receive, process and store data in order to be a useful tool. Data can be text, programs, sounds, video, graphics, etc. Some devices for entering data are keyboards, mice, scanners, pressure-sensitive tablets, or any instrument that tells the computer something. The keyboard is the most popular input device for entering text, commands, programs, and the like. (Tessler 157) Newer computers which use a GUI (pronounced gooey), or Graphical User Interface, utilize a mouse as the main device for entering commands. A mouse is a small tool with at least one button on it, and a small tracking ball at the bottom. When the mouse is slid across a surface, the ball tracks the movement on the screen and sends the information to the computer. (Tessler 155) A pressure-sensitive tablet is mainly used by graphic artists to easily draw with the computer. The artist uses a special pen to draw on the large tablet, and the tablet sends the data to the computer. Once the data is entered into the computer, it does no good until the computer can process it. This is accomplished by the millions of transistors compressed into the thumb-nail sized chip in the computer. These transistors are not at all randomly placed; they form a sequence, and together they make a circuit. A transistor alone can only turn on and off. In the ³on² state, it will permit electricity to flow; in the ³off² state, it will keep electricity from flowing. (Poole 136) However, when all the microscopic transistors are interconnected, they have the ability to control, manipulate, and move data according to the condition of other data. A computerıs chip is so ignorant, it must use a series of sixteen transistors and two resistors just to add two and two. (Poole 141) Nevertheless, this calculation can be made in just a microsecond, an example of the incredible speed of the PC. The type of chip mainly used now is known as a CISC, or Complex Instruction Set Chip. (Constable 98) Newer workstation variety computers use the RISC type of chip, which stands for Reduced Instruction Set Chip. While the ³complex² type might sound better, the architecture of the RISC chip permits it to work faster. The first generation of CISC chip was called SSI, or Small Scale Integration. SSI chips have fewer than one hundred components. (Reid 124) The period of the late 1960s is known as the era of MSI, or Medium Scale Integration. MSI chips range from one hundred to one thousand components each. (Reid 124) LSI, or Large Scale Integration, was used primarily in the 1970s, each chip containing up to ten thousand components. Chips used in the 1990s are known as VLSI, or Very Large Scale Integration, with up to a million or more components per chip. In the not-so-distant future, ULSI, or Ultra Large Scale Integration, will be the final limit of the miniaturization of the chip. The transistors will then be on the atomic level and the interconnections will be one atom apart. (Reid 124) Because further miniaturization is not practic al parallel² systems that split jobs among hundreds of processors will become common in the future. Once data is entered and processed, it will be lost forever if it is not stored. Computers can store information in a variety of ways. The computerıs permanent read-only memory, which it uses for basic tasks such as system checks, is stored in ROM, or Read Only Memory. Programs, files, and system software are stored on either a hard disk or floppy disk in most systems. The hard disk and floppy disk function similarly, but hard disks can hold much more information. They work by magnetizing and demagnetizing small areas on a plastic or metal platter. The ³read² head then moves along the tracks to read the binary information. When the program or file being read is opened, it is loaded into RAM (Random Access Memory) where it can be quickly accessed by the processor. RAM is in small chips called SIMMs, or Single Inline Memory Modules. The speed of RAM is much faster than a disk drive because there are no moving parts. The information is represented by either a one or a zero, and this amount of information is called a bit. (Constable 122) Four bits make a nybble, and two nybbles make a byte. One byte can hold one character, such as ³A² or ³?². 1024 bytes make a kilobyte, 1000 kilobytes make a megabyte, 1000 megabytes make a gigabyte, and 1000 gigabytes make a terabyte. Most personal computers have approximately eighty or so megabytes of hard drive space and either two or four megabytes of RAM on average. Most ROM on PCs is about 256 kilobytes. Machine language is the way all computer handle instructions-the simple, one or zero, yes or no, true or false boolean logic necessary for computers. (Reid 122) Boolean logic was invented by George Boole, a poor British mathematician in 1815. His new type of logic was mostly ignored until makers of computers more than a century later realized his was the ideal system of logic for the computers binary system. Machine code is the only programming ³language² the computer understands. Unfortunately, the endless and seemingly random strings of ones and zeros is almost incomprehensible by humans. Not long after the computers such as ENIAC came along, programmers began to develop simple mnemonic ³words² to stand in the place of the crude machine code. The words still had to be changed into machine code to be run, though. This simple advancement greatly helped the programmers with their tasks. Even with these improvements, the process of programming was still a mind-boggling task. The so-called high-level languages are the type used for programming in the 90s. Rarely is there ever a need today for programming in machine code. The way a high-level language works is by converting the English-based commands into machine code by way of an Assembler program. (Constable 122) There are two types of Assembler programs: Compilers and Interpreters. A compiler converts the entire program into machine code. The interpreter is only capable of converting one line at a time. The first compiler language was Fortran. Fortran became quite popular after its release in 1957 and is still used for some purposes to this day. Cobol is another high-level compiler language that has been used widely in the business world from 1960 until now. A compiler must be utilized before a program can be run. The compiler translates the program into the ones and zeros of binary machine code. There are many compiler languages used today, such as C and Pascal, named for the French genius Blaise Pascal. These two languages are the most popular high-level languages used for application development. The interpreter languages are better suited for home computers than business needs; they are less powerful, but much simpler to use. An interpreter language is translated into machine code and sent to the processor one line of code at a time. The first popular interpreter language was BASIC, or Beginnerıs All-purpose Symbolic Instruction Code, written by John Kemeny and Toms Kurtz at Dartmouth College. BASIC is still a much-used language, and is included free with many PCs sold today. BASIC was the first programming language to use the INPUT command, which allows the user to input information into the program as it is running. (Constable 29) Another newer and less popular interpreter language is Hypertalk, a language that is very English-like and easy to understand. It is included free with every Macintosh computer. There are advantages and disadvantages to both the compiler and the interpreter languages. The interpreter languages lack speed; however, because they compile as they run, they are very easily ³debugged² or fixed and changed. Before the programmer using a compiler language can try out his program, he must wait for the compiler to translate his program into machine code and then change it later. With an interpreter language, on the other hand, the ease of modification comes with the price of slower performance and limited capabilities. The history of computers, the way computers handle information, and the methods of programming all confirm that computers will never be as intelligent as the people who will design them. This essay is only for research purposes. If used, be sure to cite it properly! |
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