Internet - 1
|
|
Computers
and Part I
The device shown above is an abacus--the first "computer." An abacus takes no electricity, doesn't have to be booted up, requires no maintenance, and never crashes. The rings are flipped back and forth to represent the placement of numbers in a sequence. The abacus goes back hundreds of years and is still the preferred calculator for a few people in some countries. Today's electronic computers do the same thing--compute numbers, albeit a few billion times faster that an abacus. All of today's sophisticated software--word processors, games, editing systems, e-mail, and even the page you are viewing--can be reduced to a string of "0" and "1" numbers that a computer "computes." Even CD music and DVD movies consist of nothing more than combinations of these two numbers that are "computed" and then presented to our eyes and ears.
Although it has been assumed that the Internet was invented in the United States, there is evidence that the concept actually originated in Geneva, Switzerland. Even before U.S. scientists started using the technology in the United States, scientists in research laboratories in Geneva, had linked computers in different departments together to share their findings with each other. Even so, it was clearly scientists the United States that subsequently developed and popularized the concept.
The
World's First Computer-- It is also widely assumed that the world's first computer was the American Eniac. Actually, Alan Turing, a British Postal employee developed the first computer in England during World War II. Turing's computer, the Colossus, contained 1,000 vacuum tubes and was a major (although until recently very secret) factor in the outcome of World War II. The Colossus was developed to decode critical German encrypted messages--messages that provided information so critical that some historians say that Turning's computer shortened the war by at least two years. One historian feels that one million lives may have been saved as a result of this invention. Although Turning was by some accounts the most important hero of the war, when it was discovered that he was gay, he was so persecuted that he ended up taking his own life.
The first computers filled entire rooms and required thousands of vacuum tubes. When the transistor was invented, the size of computers suddenly shrunk to a fraction of their original size--and this development set the stage for personal computers. The
personal computer was introduced in 1975. It was the The Internet and the worldwide web are based on computers, of course. And, love them or hate them, some very basic things are important to understand. But, don't worry, we're not going into a long, technical explanation on how computers work--just what's necessary to understand and effectively get around the Internet. Although the terms Internet and the Worldwide Web are commonly used interchangeably, the worldwide web is actually only a part of the Internet. The latter includes Telnet, FTP (file transfer protocol), and other communication languages and approaches. However, when most people speak of the Internet today they are just focusing on the Worldwide Web--the part of the Internet that displays pages such as the one you are now viewing.
Today there are two major computer
platforms: Windows and Mac (Apple Computer). Linux, an operating system that is gaining popularity because of cost and security, runs on most machines. However, the downside is that there is a scarcity of programs designed for Linux and it is not considered as user-friendly as the Windows or Mac operating systems (OSs). The various Windows operating systems--primarily Windows 98, Windows XP and Windows NT/2000--run on well over 90 percent of the world's personal computers. However, when it comes to workstations used in professional agencies, the race is much closer, as you can tell from this graph. Chronological Development of the Internet
Despite some increases in speed, and despite the many technological improvements that would now be possible (note chart above), the basic Internet structure and protocol has remained about the same for decades. This is primarily because most people are still using telephone lines to access the Internet — something, incidentally, that telephone circuits were never designed for. Even though a new system would have many advantages, the introduction of a new and totally incompatible system would obviously represent a major problem — especially for the millions of users that have a major investment in the Internet as we now know it. In the last two decades the number of U.S. homes connected to the Internet has been steadily growing--at least it was until April of 2001, when there was a slight decline from the peak of 70 million.
Even so, during this time, the largest Internet service provider, America Online, announced that it had more than 30-million subscribers, an all-time high.
Regular use of the Internet is strongly related to education and race. 
Note in the graph on the left that while only about 22% of people without a high school education use the Internet, almost 90% of people with a college education regularly surf the Net. Age is also strongly related. In some cases grade school youths are much more comfortable with computers and the Internet than even their elder brothers and sisters who are in college. Note from the
graph on the right that Internet Although some families may consider the Internet a luxury, savvy businesses now see it as a necessity in today's competitive business environment. The steady Internet growth also continued in schools. Virtually 100 percent of U.S. libraries have Internet connections. Computer classrooms, especially in grade schools and high schools, continue to expand. For example, the Henrico County Public Schools in Richmond, Va. recently placed an order for 23,000 Apple iBook laptops--enough for every teacher and student in its middle and high schools. The number of colleges and universities that require computers as part of their general curriculum continues to grow, and many college dormitories are now wired for high speed Internet access. Thousands of college classes depend on the Internet for reading materials and course research, and the number of complete courses on the Internet now totals several hundred-thousand. Several institutions grant degrees solely on the basis of Internet coursework.
Millions of people no longer make out checks, address envelopes, and lick stamps to pay their bills--they simply do it all by mouse clicks. Some banks exist only on the Internet, which often means that the money they save on offices, facilities, etc., can not only be passed on to users in the form lower fees, but these institutions can also pay higher interest rates on accounts. After the series of terrorist
attacks in the United States that involved the U.S. mail and biological
materials such as anthrax, both Internet bill paying and e-mail saw
sudden spurts of growth. Although Internet advertising trails the other media in total revenue, as you can see on the right, it is showing the most rapid growth. Advertising on the Internet has a controversial history. Many purists originally felt that the Internet should be free of advertising clutter and influence. (The same views were originally lodged against broadcast advertising.) Of course without advertising these media would not have developed as rapidly and as impressively as they did. Even with all of these developments, the Internet is still in its infancy. As bandwidth limitations and standards problems are resolved, many of the barriers to the more effective use of the Internet will be removed. A major problem for education is the inability to transmit full-screen, full-motion video--a problem that should soon be resolved. Compared
to the traditional classroom, research has shown that students can do
just as well, and sometimes better, by taking well-designed Internet
courses. For students, Internet classes not only save time and money,
but they can fit into difficult work schedules. A more detailed discussion
of the future of cyberclasses can be |
Altair,
the device that Bill Gates of Microsoft, now reputed to be the world's
richest man, took an immediate interest in. And the rest, as they say,
is history. That history is graphically shown on the right.
The
3% decline (see graph) can be attributed to four things. During the
first part of 2001, a number of free Internet services went bankrupt
and thousands of people who were using these services dropped out. Some
free services started charging fees based on usage time. Many people
who signed up for high-speed DSL (digital subscriber lines) were disappointed
when providers couldn't deliver promised services. And, finally, the
economic downturn during the first part of 2001 in the United States
resulted in belt-tightening by many people, and many non-necessities
were eliminated from budgets.
use almost doubles according to race. Again, this has definite implications
for personal and professional success. 
Another
indication of the rapid growth of computer use has been the increase
in bill paying over the Internet.
|
One of the major complaints about the Internet, of course, is how slow it can be. So, first we'll examine the things that limit speed and give you some pointers on how you can speed things up--especially when "surfing the net" from home.
The speed of your computer's CPU (central processing unit--a computer chip that's the heart of your computer) will to a large extent determine the speed of software operations.
Every six months or so the CPU chip makers are able to develop a faster CPU. This is one of the reasons computers quickly become obsolete. Part of a motherboard (the main circuit board area of the computer) is shown above. Although there is a definite element of ego behind having the "fastest computer on the block," there is also a practical element. As computer programs become more complex, computer resources--especially speed--must also advance, simply to keep pace.
CPU speed is only one of several factors that determine how fast things will happen in your computer. The amount of memory your computer has is also important. Most computers today have at least 256 megs (megabits) of RAM (random-access memory). When your computer boots up (starts), needed programs are loaded into RAM, where information can be quickly accessed. RAM is volatile memory because all of the information in RAM disappears when the power to your computer shuts off. This, of course, includes whatever data that you may have been reading or working on that wasn't saved on a hard or floppy disk. The hard drive in your computer represents nonvolatile memory, or information that is recorded on a medium--in this case a hard drive--that stays there once the power to your computer is shut off. Thus, any information you want available the next time you boot up your computer must be saved on a disk drive. The
speed of RAM (how quickly it can absorb and transmit information) is
also important to computer speed. RAM speed is measured in nanoseconds
(ns), or billionths of a second. In terms of speed, the smaller the
number, the better. A typical computer chip is shown on the right. As computer programs get bigger and more complex, there is also a need to add more computer RAM so that things won't slow down. Keep in mind that program and data information that won't fit into RAM when the computer boots up must be read from the hard drive, which is a slower process than using RAM for the same purpose. Thus, the more RAM the better.
Hard disks or hard drives were invented by IBM in 1956. The first one could only hold about 5MB of data — by today's standards not even enough to hold a respectable word processing program. Even so, IBM rented their hard drive to users for $3,100.00 a month. Using that cost ratio as a standard, one of today's (very small) computer hard drives would sell for hundreds of millions of dollars. (This has been one of the few things in life where you have been able to get more for less money on almost a monthly basis.)
A
cutaway view of a The read-write heads move very fast; they can flip back and forth over the total surface of the disk at least 50 times a second, while, at the same time, gathering or recording data. The hard drive shown above has four platters and requires several read-write heads for the top and bottom surfaces of each platter. As the platter spins and the read-write heads swing back and forth over the disk's surface, digital data is magnetically transferred to or read from invisible microscopic tracks on the disk's surface.
Note that in the drawing on the left a sector or block of data is one segment of a track. Each sector contains a fixed number of bytes of information--generally 256 or 512 bytes. (These tracks are actually microscopic, but we've enlarged them so they could be seen in the drawing.) For any number of reasons, including an unexpected loss of power, you should regularly save the information you are working on to the nonvolatile memory of your computer's hard drive. (Of course, most of us learn this the hard way when we lose an hour's work!) Hard drives also have speed considerations. The speed at which data can be written to and read from a hard drive represents a major limiting factor in computer speed. If you see the specifications on two hard drives, for example--one of which reads and writes information at 12ms (millionths of a second) and the other one at 8ms--you know that the smaller number is better because it represents less time. When billions of bits of data are regularly being written to and read from a hard drive, this becomes very important to computer speed. The platters or disks rotate at a constant speed, which, depending on the design, may range from 3,600 to 7,200 rpm (revolutions per minute) The soft "whining sound you hear from a computer when it's running is probably the hard drive spinning. Although hard drives can have life spans of many thousands of hours, all of them at some time will fail (crash). Like earthquakes in California, it isn't a matter of if, it's a matter of when. This can be caused by a strong jolt that crashes a head into the surface of a platter, or just by a part eventually wearing out. When a hard drive fails--and that's often without any notice that a problem is even looming--you lose all of the data on the hard drive, which generally represents all of your data and programs. The good news is that since computers tend to be obsolete after a few years, hard drives generally outlast the practical life of the computer. But, of course, you can't count on that. Therefore, you need to keep the CDs of all your original programs along with their original installation keys, so the programs can be reinstalled. Even if your hard drive doesn't crash, you sometimes have to reinstall programs when information gets corrupted on your hard drive by a virus or by a scrambled write-to-disk operation. And
speaking of viruses, with destructive viruses appearing on a daily basis,
it's essential that you have a good anti-virus program installed in
your computer--especially if you spend time on the Internet. The graph on the right shows how much cyberattacks and viruses cost U.S. businesses . Note that about 5% of businesses (in red) had to pay out a half-million dollars or more to fix resulting problems, and 32% (in yellow) paid up to $10,000. In 2004 and 2005, the number of viruses rose sharply. Many, if not most, come from outside the United States. Corporations such as Microsoft are offering large rewards for turning in anyone who releases a virus on the Internet. A number of virus writers are now serving prison terms for cyberattacks. E-mail is a favorite target of virus scoundrels. Savvy users never open an e-mail attachment unless they know and trust the sender. Files that have attachments with .doc and .exe suffixes can easily contain viruses. A
good virus program can usually catch and stop these viruses from infecting
your computer--if you regularly update your virus definition files.
The leading companies have programs that do this automatically. A virus
can wipe out everything on a hard drive, It's also important to regularly update your computer's operating system. These generally come in the form of "patches" that are available from the company's website. Because of potential problems, you need to keep at least one good copy of all of your important data on a medium such as a jump drive (shown on the left), a floppy disk, or a recordable CD. This is called backing up your data. There seems to be a "Murpy's Law" involved here: it's only the original data that you failed to back up that will unexpectedly disappear or get destroyed! In the next section we'll look at how data gets from your computer to the Internet and back. You might be amazed that the process works at all! |
The
latest computer CPUs operate at more than 2 GHz (gigahertz, or billion
operations per second).
hard
drive is shown here. The read-write head (the silver arm you see suspended
over the top of the rust-colored platter), rides on an ultra-thin
layer of air as the platter (disk) spins. This separation is critical,
because if one of these heads comes in direct contact with highly-polished
surface of the a platter, it will scratch it and possibly damage the
head. In either case, major problems result.
These
magnetic traces are organized into tracks and sectors.
requiring
many hours--even days--of work to restore everything. |
To next module To
index © 1996 - 2005, All Rights Reserved.
|
