Реферат: A Long Way From Univac Essay Research
A Long Way From Univac Essay, Research Paper
Adv. Eng. 9
A Long Way From Univac
Can you imagine a world without computers? You most probably interact with some form of a computer every day of your life. Computers are the most important advancement our society has ever seen. They have an interesting history, many interesting inner components, they are used nearly everywhere, and continue to advance incredibly fast. Because the field of computers is so broad, this paper will focus mainly on personal computers.
Although computers have been evolving for quite some time, they really didn+t gain popularity until the introduction of the personal computer. In 1977, Steve Jobs, co-founder of the Apple Computer Company, unveiled what is generally considered to be the first personal computer, the Apple II. This computer was introduced on April 16, 1977, at the First West Coast Computer Faire, in San Francisco. In 1981, the International Business Machines Company introduced the first IBM PC. Unlike Apple, IBM used a policy of open architecture for their computer. They bought all of their components from the lowest bidder, such as the 8086 and 8088 microprocessor chips, made by a Intel, a Hillsboro, Oregon company. When IBM+s computer+s design had been finalized, they shared most of the inner workings of the computer with everyone. IBM hoped that this would encourage companies to manufacture computers that were compatible
with theirs, and that in turn, would cause software companies to create operating systems, or OS, and other programs for the |IBM CompatibleX line of computers. One of the computer manufacturers was a Texas company called Compaq. A company called Dell Computers was the first |factory directX computer seller. A small Redmond, Washington company called Microsoft made a large amount of software for the |IBM CompatibleX line of computers. This open architecture policy of IBM was not without it+s flaws, however. IBM lost some business to the |clonesX who could offer more speed, more memory, or a smaller price tag. IBM had considered this an acceptable loss. One of the few components of the IBM PC that was kept from the clone manufacturers was the Basic Input Output System, or BIOS. This program, which was usually etched permanently on a chip, controlled the interactions between the internal hard and floppy drives, the external drives, printers, and monitors, etc. Clone manufactures had to make their own versions of an input output system. Some manufacturers copied the IBM BIOS exactly, such as Eagle Computers, and Corona Data Systems. This is one adverse affect that IBM had not thought of. However, all of IBM+s copyright violation lawsuits against these companies ended in IBM+s favor. IBM has continued to grow to this day, however, the clone manufacturers make far more personal computers than IBM, while IBM makes more business machines, and the Power PC microprocessor, used in Macintosh computers. IBM clone are now made by Packard Bell, Sony, Acer, Gateway 2000, and more. The clones have continued to use software and operating systems made by Microsoft, including: DOS (Disk
Operating System), Windows, Windows 95, and Windows NT. The clones also primarily use microprocessors manufactured by Intel, including the 8086, 8088, 80286, 80386, 80486, Pentium and Pentium Pro, which offer speeds over 200 megahertz, and will be even faster in the near future (Silver 7-28).
Apple took a somewhat different course during this period. Not willing to enter the IBM clone manufacturing market, Apple continued to make their own kind of computers. They made minor improvements on the Apple II line, but eventually decided they needed to make a new type of computer. They first introduced the Apple III in September of 1980. It was a dismal failure. The first buyers encountered numerous system errors and failures, because of a poor OS. Besides that, it was poorly manufactured, with improperly fitting circuitry, loose wires and screws, etc. The later released Apple III+ did poorly because of it+s brother+s poor debut. The next big release was the Lisa in January of 1983. It was the first personal computer with a mouse, and nice graphic capabilities. Experiments showed that it was 20 times as easy to use as the IBM PC, and it drew enormous praise from computer magazines. It had flaws too, however. It strained the power of the aging Motorola 68000 microprocessor, so it lost in speed tests to the IBM PC. It also came with a $10,000 price tag, over twice as much as most IBM clones. The Lisa failed, not as catastrophically as the Apple III, but failed, nevertheless. Apple had but one more ace up their sleeve, and they released it in January of 1984. They called it the Macintosh, and it was very
popular. Apple still uses the Macintosh series of computers to this day. In 1995, Apple finally allowed other companies to use their OS, and manufacture clones. Some clone manufacturers include: Power Computing, Umax, Radius, and Motorola. Unlike IBM, Apple still sells more computers than it+s clones, but Power Computing is steadily gaining in sales. Macintoshes and Mac clones use System 6, System 7, System 7.1, System 7.5, and System 7.6, all made by Apple. Macintoshes and their clones use microprocessors manufactured by Motorola, including, 68000, 68881, 68020, 68030, 68040, and the Power PC 601, 603, and 604, made by Motorola and IBM, with speeds up to 225 megahertz, and a 603e, available in January of 1997, operating at 300 megahertz (Hassig 45-68)
Computers have many interesting components, including: motherboards, microprocessors, FPUs (Floating Point Unit), hard disk drives, floppy disk drives (5.25X and 3.5X), CD ROM drives (Compact Disc Read Only Memory), cartridge drives, ROM chips (Read Only Memory), RAM (Random Access Memory), VRAM (Video Random Access Memory), NuBus or PCI expansion cards (Peripheral Complement Interface), monitors, keyboards, mice, speakers, microphones, printers, network systems, and modems. The motherboard is what the microprocessor, FPU, ROM, RAM, VRAM and all the circuitry are attached to. The microprocessor, also called a CPU (Central Processing Unit) and FPU are what everything goes through, and tell what to do with data. Most CPUs operate from 2.5 megahertz (MHz, millions of cycles per second) to 300
MHz. The hard disk holds large amounts of data for a long time. Most hard disks can hold from 1 megabyte (MB) to 10 gigabytes (GB). *NOTE: (1 GB is 1,024 MB, 1 MB is 1,024 kilobytes (K), 1 K is 1,024 bytes, 1 byte is 8 bits, and a bit is an on/off code (binary code uses 0 for off and 1 for on), therefore a 10 GB hard disk can have 8,589,934,592 bits!). Floppy disks are for putting small amounts data on, and being able to take them with you. The old 5.25X disks held a few K of data, while the new 3.5X type holds 800 K or 1.4 MB. CD ROMs are relatively new. They have very fine lines on their surface read by a laser, and can usually hold 650 MB of data (which is unchangeable). CD ROM drives range in disc reading time from 1X (real time, 150 K/sec) to 15X (2.2 MB/sec). Cartridges store large amounts of data and are removable, like floppy disks. They can store up to 1 GB, and come in all shapes and sizes, each type with a different drive. ROM is unchangeable data soldered on the motherboard. RAM is memory the computer uses for immediate access, such as open applications. Everything on the RAM is lost when the computer is shut down. VRAM is used to display a higher resolution or greater color depth on the monitor. 512 K or 1 MB is the standard amount on most computers, and 8 MB is the most available. The resolution ranges from 400 by 300 pixels to 1,920 by 1,440 pixels. The color depth ranges from 1 bit (black and white) to 36 bit (68,719,476,470 colors). NuBus and PCI expansion cards add special features to computers, such as receiving TV transmissions. Monitors display images given to them by VRAM. They range in size from 9 to 21 inches diagonally. Keyboards input data into the computer. Mice have a
track ball that moves around inside, causing a cursor to move across the screen. Speakers amplify the sound output of a computer. Microphones allow sounds to be recorded on a computer. Printers allow computers to put data on paper. Network systems allow data to be easily transmitted from one computer to another. Modems allow data to be transmitted through telephone wires. They have variable speeds from 300 bytes per second (BPS) to 57,600 BPS (Rizzo 5-21).
Today, computers are utilized in just about every field imaginable. A caution for the future of computers is that they could go berserk or, if they had a working artificial intelligence, they could make mankind completely obsolete. Computers have evolved, and will continue to evolve faster than any tech technology to date. Therefore, it is impossible to fathom where computers will be in a thousand, or even a hundred years. One thing, however, is certain: computers are the most important advancement our society has ever seen.
Rizzo, John and K. Daniel Clarke. How Macs Work. New York: Ziff-Davis Press, 1996.
Hassig, Lee, Margery A. duMond, Esther Ferrington, et al. The Personal Computer. Richmond: Time Life, 1989.
Silver, Gerald A. and Myrna L. Silver. Computers and Information Processing. New York: HarperCollins Publishers, 1993.