Computers and Computer Systems

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Computers and Computer Systems

A computer is a programmable device that can automatically perform a sequence of calculations or other operations on data once programmed for the task. It can store, retrieve, and process data according to internal instructions. A computer may be either digital, analog, or hybrid, although most in operation today are digital. Digital computers express variables as numbers, usually in the binary system. They are used for general purposes, whereas analog computers are built for specific tasks, typically scientific or technical. The term "computer" is usually synonymous with digital computer, and computers for business are exclusively digital.

ELEMENTS OF THE COMPUTER SYSTEM

The core, computing part of a computer is its central processing unit (CPU), or processor. It comprises an arithmetic-logic unit to carry out calculations, main memory to temporarily store data for processing, and a control unit to control the transfer of data between memory, input and output sources, and the arithmetic-logic unit. A computer is not fully functional without various peripheral devices, however. These are typically connected to a computer through cables, although some may be built into the same unit with the CPU. These include devices for the input of data, such as keyboards, mice, trackballs, scanners, light pens, modems, magnetic strip card readers, and microphones, as well as items for the output of data, such as monitors, printers, plotters, loudspeakers, earphones, and modems. In addition to these input/output devices, other types of peripherals include computer data storage devices for auxiliary memory storage, where data is saved even when the computer is turned off. These devices most often are magnetic tape drives, magnetic disk drives, or optical disk drives.

Finally, for a digital computer to function automatically, it requires programs, or sets of instructions written in computer-readable code. To be distinguished from the physical or hardware components of a computer, programs are collectively referred to as software.

A computer system, therefore, is a computer combined with peripheral equipment and software so that it can perform desired functions. Often the terms "computer" and "computer system" are used interchangeably, especially when peripheral devices are built into the same unit as the computer or when a system is sold and installed as a package. The term "computer system," however, may also refer to a configuration of hardware and software designed for a specific purpose, such as a manufacturing control system, a library automation system, or an accounting system. Or it may refer to a network of multiple computers linked together so that they can share software, data, and peripheral equipment.

Computers tend to be categorized by size and power, although advancements in computers' processing power have blurred the distinctions between traditional categories. Power and speed are influenced by the size of a computer's internal storage units, called words, which determine the amount of data it can process at once and is measured in bits (binary digits). Computer speed is also determined by its clock speed, which is measured in megahertz. Additionally, the amount of main memory a computer has, which is measured in bytes (or more precisely, kilobytes, megabytes, or gigabytes) of RAM (random access memory), plays a role in determining how much data it can process. The amount of memory that auxiliary storage devices can hold also determines the capabilities of a computer system.

THE MICROCOMPUTER

The development of the microprocessor, a CPU on a single integrated-circuit chip, enabled the development of affordable single-user microcomputers for the first time. The slow processing power of the early microcomputers, however, made them attractive only to hobbyists and not to the business market. In 1977, however, the personal computer industry got under way with the introduction of off-the-shelf home computers from three manufacturers.

The term "personal computer" (PC) was coined by IBM with the launch of its PC in 1981. This model became an instant success and set the standard for the microcomputer industry. By the early 1990s personal computers had become the fastest-growing category of computers. This was largely due to the adoption of their use in businesses of all sizes. The availability of these small, inexpensive computers brought computer technology to even the smallest of enterprises.

The most recent category of microcomputer to enter the business world is the portable computer. These small and light—but increasingly powerful—computers are commonly known as laptop or notebook computers. Laptop computers have the same power as desktop personal computers, but are built more compactly and use flat screen monitors, usually using liquid crystal display, that fold down to form a slim unit that fits in a briefcase and usually weigh under 15 pounds. A notebook computer is one that weighs under 6 pounds and may or may not have a full-size keyboard. A pocket computer is a hand-held calculator-size computer. A personal digital assistant is a pocket computer that uses a pen and tablet for input, has a fax/modem card, and is combined with the capabilities of a cellular telephone for remote data communications. Portable computers are increasingly popular among businesspeople who travel, such as executives or sales representatives.

Open Systems

Today, most computer systems are "open"—compatible with computer hardware and software from different manufacturers. In the past, all components of a computer system originated from the same manufacturer. There were no industry-wide standards. As a result, printers, monitors, and other peripheral equipment from one manufacturer would not operate when matched with the computer of another manufacturer. More significantly, software could only run on the specific computer brand for which it was designed. Today, however, "open systems," wherein various equipment from different manufacturers can be matched together, is common. Open systems are especially popular among small business owners because they allow enterprises to upgrade or expand their computer systems more easily and cheaply. Open systems provide business owners with more buying options, enable them to minimize expenses of employee retraining on new systems, and give them greater freedom to share computer files with outside clients or vendors.

Networking

Computers on a network are physically linked by cables and use network software in conjunction with the operating system software. Depending on the hardware and software used, different types of computers may be put on the same network. This may involve computers of different sizes—such as mainframes, mid-ranges, and microcomputers—or computers and peripherals of different manufacturers, which the trend toward open systems has facilitated. Local area networks (LANs) link computers within a limited geographical area, while Wide area networks (WANs) connect computers in different geographic regions. Networks may have various architectures which determine whether computers on the network can act independently. A commonly used system architecture is client-server, whereby a server computer is designated as the one storing and processing data and is accessed by multiple users each at a client computer.

LANs have transformed how employees within an organization use computers. In organizations where employees formerly accessed midrange computers through "dumb" terminals, these employees now typically have more capabilities. These users have their own personal computers at their desks, but are still able to access needed data from a midrange or other server through the network. Whereas smaller businesses typically favor LANs, WANs are often used by companies with multiple facilities located over a wide geographic area. After all, under a WAN system, a company's databases can be accessed at headquarters in one city, at a manufacturing plant in other city, and at sales offices in other locations.

BUSINESS USAGE OF COMPUTERS

Computers are used in government, industry, nonprofit and nongovernmental organizations, and in the home, but their impact has been greatest in business and industry. The competitive nature of business has created demands for continuous advances in computer technology and systems design. Meanwhile, the declining prices of computer systems and their increasing power and utility has led more and more enterprises to invest in computer systems for an ever-widening range of business functions. Today, computers are used to process data in all aspects of a business enterprise: product design and development, manufacturing, inventory control and distribution, quality control, sales and marketing, service data, accounting, and personnel management. They are also used in businesses of all sizes and in all industry segments, including manufacturing, wholesale, retail, services, mining, agriculture, transportation, and communications.

The most common business uses of a computer system are database management, financial management and accounting, and word processing. Companies use database management systems to keep track of changing information in databases on such subjects as clients, vendors, employees, inventory, supplies, product orders, and service requests. Financial and accounting systems are used for a variety of mathematical calculations on large volumes of numeric data, whether in the basic functions of financial service companies or in the accounting activities of firms. Computers equipped with spreadsheet or database management software, meanwhile, are used by accounts payable, accounts receivable, and payroll departments to process and tabulate financial data and analyze their cash flow situations. Finally, word processing is ubiquitous and is used to create a wide range of documents, including internal memos, correspondence with outside entities, public relations materials, and products (in publishing, advertising, and other industries).

Databases may also be used to help make strategic decisions through the use of software based on artificial intelligence. A database system may include—in addition to records and statistics of products, services, clients, etc.—information about past human experience within a specific field. This is referred to as a knowledge base. Examples of expert system usage include business forecasting activities such as investment analysis, financial planning, insurance underwriting, and fraud risk prediction. Expert systems are also used in activities associated with regulatory compliance, contract bidding, complex production control, customer support, and training.

COMPUTER SYSTEMS AND SMALL BUSINESS

For most small businesses, jumping into the world of computers is a competitive requirement, especially with the advent of the Internet. But computer system purchases can be daunting for entrepreneurs and established business owners alike. After all, small business enterprises typically have less margin for error than their big business brethren. Given this reality, it is very important for owners and managers to make wise choices when choosing and maintaining computers and computer systems. Four major areas that business owners and managers need to consider when weighing computer options are: 1) your company's overall business strategy; 2) the needs of your customers; 3) the needs of your workforce; and 3) the technology's total cost of ownership (TCO).

Company Strategy

"It is common to view computer systems technology as a stand-alone entity when, in fact, it should be regarded as one of the larger-scale and more widely-used business tools," wrote Richard Hensley in Cincinnati Business Courier. "[Computer systems technology is] a tool that is critical for achieving the overall corporate strategy…. Although it may well exist in the owner's mind, many small and mid-sized companies have no detailed written system strategy. It is not surprising then, that many of the systems technology implementation decisions are more reactive than they are strategically based. Competitive pressures, the need to catch up to the marketplace, and internal growth tend to force buying decisions." Instead, system purchasing decisions should be used proactively as an opportunity to evaluate overall strategies and assess the effectiveness of current operational processes.

Customer Needs

Business owners also need to ensure that their chosen computer system meets the needs of customers. Is ongoing communication with clients a critical component of your business? If so, then your system should be equipped with features that allow you and your client to communicate via computer in a timely and effective fashion. Does your business's health hinge on processing customer orders and generating invoices? If so, make sure your system can easily handle such requirements.

Workforce Needs

Whether introducing a new computer system or making changes to an existing system, businesses inevitably change the ways in which their employees work, and this factor must be taken into consideration. "It is not unusual to experience some resistance from employees who are reluctant to accept departure from the status quo," said Hensley. "Such resistance can often be greatly reduced by involving the affected employees in the development of, or modification to, the system. They can provide practical information on what works well within the current system and what doesn't. Once the changes have been implemented, establish a training program and support structure for all users. This will maximize the benefits of the system and better equip employees to achieve the results expected from the change." In addition, companies need to make sure that computer technology is distributed in an intelligent fashion. Computers should be allocated according to need, not ranking.

Total Cost of Ownership

Many small businesses neglect to consider the accumulated costs associated with various computer systems when making their hardware decisions. In addition to the original price tag, companies need to weigh hidden information technology costs associated with the purchase. These costs, known as total cost of ownership (TCO), include technical support, administrative costs, wasteful user operations, and supplementary expenses (printer ink and paper costs, electricity, etc.). Another factor that should be considered is the equipment's useful life. After all, as Hensley noted, "to assure the capability to produce relevant information, technology systems require scheduled investments." Business owners that ignore this reality do so at their peril, suggest experts. "When it comes to cutting costs, one of your first instincts may be to hold on to your PCs as long as you can, thinking the less money you spend on new technology, the better," wrote Heather Page in Entrepreneur. Actually, though, such reasoning ultimately raises business costs. "Having several generations of hardware, software and operating systems increases the complexity of your PC environment, thus increasing your costs," explained Page. "Not only do you have to maintain technical expertise in older technologies, but you also have to find ways for older equipment to work with the new technologies and develop all your custom applications to support multiple environments."

Given today's fast-changing business environment, then, system upgrades are a fact of life. As Joel Dreyfuss noted in Fortune, "if you don't have the latest and (always) greatest software and hardware on your business computers, your vendors and employees can make you feel that you're just one step away from quill pens and parchment." But upgrade initiatives should not be approved impulsively. Instead, business owners and managers should conduct appropriate cost-benefit analysis, weighing such issues as installation and training costs, compatibility with other systems, usefulness of new features, and current ability to meet business needs, before investing in major computer system upgrades.