Applications of IT
IT, as defined in this chapter, reflects the combination of three key technologies: digital computing, data storage, and the ability to transmit digital signals through telecommunications networks. Rapid changes in semiconductor technology, information storage, and networking, combined with advances in software, have enabled new applications, cost reductions, and the widespread diffusion of IT. The expanding array of applications makes IT more useful and further fuels the expansion of IT.
Enormous improvements in the performance of integrated circuits and cost reductions brought about by rapid miniaturization have driven much of the advances in IT. See sidebar, "Moore's Law."
A related trend is the migration of computing into other devices and equipment. This is not a new trendautomobiles have been major users of microprocessors since the late 1970sbut as semiconductor chips become more powerful and less expensive, they are becoming increasingly ubiquitous. Also, new capabilities are being added to chips. These include microelectromechanical systems (MEMs), such as sensors and actuators, and digital signal processors that enable cost reductions and extend IT into new types of devices. Examples of MEM devices include ink-jet printer cartridges, hard disk drive heads, accelerometers that deploy car airbags, and chemical and environmental sensors (Gulliksen 2000). Trends toward improvements in microelectronics and MEMs are expected to continue. See sidebar, "Nanoscale Electronics."
Disk drives and other forms of information storage reflect similar improvements in cost and performance. (See figure 8-2 .) As a consequence, the amount of information in digital form has expanded greatly. Estimates of the amount of original information (excluding copies and reproductions) suggest that information on disk drives now constitutes the majority of information (Lyman and Varian 2000). (See appendix table 8-2.) Increasingly, much of this information is available on-line.
Computers, reflecting the improvements in their components, have shown similar dramatic improvements in performance. Due to improvements in semiconductors, storage, and other components, price declines in computers (adjusted for quality) have actually accelerated since 1995. (See figure 8-3 .)
The third trend is the growth of networks. Computers are increasingly
connected in networks, including local area networks and wide area
networks. Many early commercial computer networks, such as those
used by automated teller machines and airline reservation systems,
used proprietary systems that required specialized software or hardware
(or both). Increasingly, organizations are using open-standard,
Internet-based systems for networks.
As people have been able to interconnect and share information with
each other, the value of IT has increased. See sidebar "Metcalfe's Law."
The growth in networking has been enabled by rapid advances in optical networking. In 1990, a single optical fiber could transmit about 1 billion bits per second; by 2000, a single fiber could transmit nearly 1 trillion bits per second (Optoelectronics Industry Development Association 2001).
The growth in networking is best illustrated by the rapid growth of the Internet. Worldwide, there were nearly 100 million Internet hostscomputers connected to the Internetin July 2000, up from about 30 million at the beginning of 1998. (See figure 8-4 .) Networking is evolving in several ways: more people and devices are becoming connected to the network, the speed and capacity of connections are increasing, and more people are obtaining wireless connections. See sidebar, "Wireless Networking."
Applications of IT
A fourth trend is the ever-increasing array of applications that make IT more useful. Computers were originally used primarily for data processing. As they became more powerful and convenient, applications expanded. Word processing, spreadsheets, and database programs were among the early minicomputer and PC applications. Over the past two decades, innovations in software have enabled applications to expand to include educational software, desktop publishing, computer-aided design and manufacturing, games, modeling and simulation, networking and communications software, electronic mail, the World Wide Web, digital imaging and photography, audio and video applications, electronic commerce applications, groupware, file sharing, search engines, and many others. The growth and diversity of applications greatly increase the utility of IT, leading to its further expansion.
In the 1960s, computers were used primarily in the R&D community and in the offices of large companies and agencies. Over the past few decades, the expansion of applications has contributed to the rapid diffusion of IT to affect nearly everyone, not just the relatively few people in computer-intensive jobs. IT has become common in schools, libraries, homes, offices, and businesses. For example, corner grocery stores use IT for a variety of electronic transactions such as debit and credit payments, and automobile repair shops use IT to diagnose problems and search for parts from dealers. New IT applications are still developing rapidly; for example, instant messaging and peer-to-peer communication systems such as Napster are examples that have become popular in the past 2 years. See sidebar, "Peer-to-Peer Applications."