THE COMPUTER ADVANTAGE
Before the early 1980s, computers were unknown to the average person. Many people had
never even seen a computer, let alone used one. The few computers that existed were relatively large,
bulky devices confined to secure computer centers in corporate or government facilities. Referred to as
mainframes, these computers were maintenance intensive, requiring special climate-controlled
conditions and several full-time operators for each machine. Because early mainframes were expensive
and difficult to operate, usage was restricted to computer programmers and scientists, who used them
to perform complex operations, such as processing payrolls and designing sophisticated military
Beginning in the early 1980s, the computer world changed dramatically with the introduction of
microcomputers, also called personal computers (PCs). These relatively small computers were
considerably more affordable and much easier to use than their mainframe ancestors. Within a few
years, ownership of personal computers became widespread in the workplace, and today, the personal
computer is a standard appliance in homes and schools.
Today’s computers come in a variety of shapes and sizes and differ significantly in computing
capability, price, and speed. Whatever their size, cost, or power, all computers offer advantages over
manual technologies in the areas of speed, accuracy, versatility, storage capabilities, and
Computers operate with lightening-like speed, and processing speeds are increasing as
computer manufacturers introduce new and improved models. Contemporary personal computers are
capable of executing billions of program instructions in one second. Some larger computers, such as
supercomputers, can execute trillions of instructions per second, a rate important for processing huge
amounts of data involved in forecasting weather, monitoring space shuttle flights, and managing other
People sometimes blame human errors on a computer. In truth, if a computer user enters
correct data and uses accurate programs, computers are extremely accurate. A popular expression
among computers professionals is “garbage in—garbage out” (GIGO), which means that if inaccurate
programs and/or data are entered into a computer for processing, the resulting output will also be
inaccurate. The computer user is responsible for entering data correctly and making certain that
programs are correct.
Computers are perhaps the most versatile of all machines or devices. They can perform a variety
of personal, business, and scientific applications. Families use computers for entertainment,
communications, budgeting, online shopping, completing homework assignments, playing games, and
listening to music. Banks conduct money transfers, account withdrawals, and the payment of checks via
computer. Retailers use computers to process sales transactions and to check on the availability of
products. Manufacturers can manage their entire production, warehousing, and selling processes with
computerized systems. Schools access computers for keeping records, conducting distance learning
classes, scheduling events, and analyzing budgets. Universities, government agencies, hospitals, and
scientific organizations conduct life-enhancing research using computers. Perhaps the most ambitious
such computer-based scientific research of all time is the Human Genome Project. Completed in April of
2003, this program was more than two years ahead of schedule and at a cost considerably lower than
originally forecast. This project represented an international effort to sequence three billion DNA
(deoxyribonucleic acid) letters in the human genome, which is the collection of gene types that comprise
every person. Scientists from all over the world can now access the genome database and use the
information to research ways to improve human health and fight disease.
Storage is a defining computer characteristic and is one of the features that revolutionized early
computing, for it made computers incredibly flexible. A computer is capable of accepting and storing
programs and data. Once stored in the computer, a user can access a program again and again to
process different data. Computers can store huge amounts of data in comparably tiny physical spaces.
For example, one compact disk can store about 109,000 pages of magazine text, and the capacities of
internal storage devices are many times larger.
Most modern computers contain special equipment and programs that allow them to
communicate with other computers through telephone lines, cable connections, and satellites. A
structure in which computers are linked together using special programs and equipment is a network.
Newer communications technologies allow users to exchange information over wireless networks using
wireless devices such as personal digital assistants (PDAs), notebook computers, and cell phones.
A network can be relatively small or quite large. A local area network (LAN) is one confined to a
relatively small geographical area, such as a building, factory, or college campus. A wide area network
(WAN) spans a large geographical area and might connect a company’s manufacturing plants dispersed
throughout North America. Constant, quick connections along with other computer technologies have
helped boost productivity for manufacturers.