Information is input to a computer in a variety of ways. The basic and most recognized computer input device is the keyboard. Although new in­put technologies continue to be developed, the keyboard continues to serve as the most widely used input device. Today, most computers are equipped with a keyboard and mouse. Other input devices that may also be used are discussed in the following sections.

Pointing devices

A pointing device is a computer hardware com­ponent that allows a user to input data or give commands to a computer. The most common pointing device by far is the mouse. Another commonly used pointing device is the trackball. A trackball is a stationary ball that can be rolled in place to move the cursor on the screen. Trackball rollers are often installed within a keyboard. They may also be attached to the side of a keyboard as a removable accessory.

The digital pen, also called a stylus or elec­tronic pen, is another pointing device that can be used to select objects, draw, give commands, or write electronically on the screen. This pointing device is used with a touchpad or a touch screen. A touchpad or touch screen senses motion and pressure by the digital pen to control the motion of the onscreen pointer or to enter handwriting. With some touch screens, the individual can use his or her finger to select commands or provide input to the computer.

The most recognizable use of an electronic pen is in retail businesses where it is used to electron­ically record signatures used to authorize credit card purchases. Touch screens are found in a va­riety of applications including airports (used as a self-check-in system), restaurants (used as an or­der entry system), petrol stations (used to select fuel and method of payment), and banking (used to complete banking and financial transactions).

The digital pen is also used with a graphics tablet, which is an input device that allows users to draw images and graphics in much the same way as with a pencil and paper. Using a digital pen, the user creates the image on the tablet and the image is displayed on a computer monitor. Graphics tablets are available in a variety of formats and price ranges and typically connect to a computer through a USB connection.

Scanner

Scanners are commonly used computer input devices. A scanner is used to capture an image in digital form and transfer that information to a computer. Original images can be in the form of a printed document, handwritten document, pho­tograph, drawing, or other graphic image. Once the information is scanned, it can be resized, inserted into other documents, posted on a Web page, sent as an email attachment, printed or treated like any other digital image.

Some scanners are equipped to work with software programs to perform optical character recognition (OCR). This technology recognizes handwritten or typed characters and converts them to an electronic form as text rather than images. The text can be edited in a word processing program. OCR technology has been used by the United States Postal Service to sort mail since the late 1960s. OCR technology is used by businesses to scan printed documents that need to be edited and revised. Because handwritten text varies widely from individual to individual, it is difficult to accurately translate handwritten information.

Digital cameras

Digital cameras allow users to take pictures that are automatically captured as digital files. The software that comes with the camera then takes the pictures from the camera and transfers the files directly to the computer. Most digital cameras are multifunctional in that they allow users to record sound and or video as well as photographs.

When a digital camera is used in conjunction with a computer, users can insert pictures into a variety of software applications where they can be edited, printed, faxed, or included with email messages. In addition, photographs can be in­corporated into electronic presentations; posted on Websites; or included in newsletters, reports, or memos. There are also many electronic devices that include digital cameras as a component. For example, many mobile telephones and PDAs contain an internal digital camera. Pictures taken with these devices can be transferred to notebook or personal computers through a USB or wireless connection or sent as an email.

Speech recognition

Speech recognition is the process of converting spoken words into digital form. You may have heard of these systems by other names, such as voice input system, voice recognition system, or computer speech recognition. Regardless of the name used, these systems require the use of a microphone or headset as well as an appropriate software package. Although speech recognition technology was originally developed for people who found it difficult to use a keyboard or mouse, it has evolved into a system that is used in a variety of business situations. Some com­puter operating system programs, such as Office 365 (Cortana), include speech recognition. Application programs, such as Dragon Naturally Speaking®, are also popular with speech recogni­tion users.

Advances in speech recognition continue to make the technology easier to use and more accurate. Programs for recognizing a few isolated words, such as telephone voice navigation sys­tems, work for almost every user. As the accuracy and ease of use have increased, speech recogni­tion systems have increasingly been incorporated into portable PCs, mobile devices, cell phones, and CPS systems to allow hands-free operation. Other similar systems are used to control ma­chines, robots, and other electronic equipment such as that used by doctors during surgical procedures.

Medical and legal transcriptions are the most frequently used speech recognition applications; however, speech recognition technology is also used for querying databases and giving com­mands to computer-based systems. When using continuous speech programs (such as a dictation program) the user must take the time to train the software to recognize his or her speech patterns. Training involves the user reading aloud samples of text. With the growing power of personal com­puters, the accuracy of speech recognition has improved markedly, making it an important input method.