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 weaponry.

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 size 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 communications capabilities.

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 data-intensive applications.

People sometimes blame human errors and mistakes 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 the 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, cell phones, and pagers.