Computer Basics 1 Identify and describe the most common input devices Identify and describe the most common output devices Identify and describe storage devices Identify and describe how input and output devices are connected to the computer 2 However, it needs help! Input, which is the data or instructions, must be entered into the computer. After the data is entered and processed, it needs to be “presented” to the user. We have special devices for these tasks and refer to them as input and output devices. 3 •Input devices enable you to input data and commands into the computer. •Output devices enable the computer to give you the results for the processed data. •Some devices can perform both of these tasks. The fax machine and modems are examples of this, as both these devices send (output) and receive (input) data over communications media. 4 Input devices enable you to input data and commands into the computer. The type of input device used is determined by the task to be completed. An input device can be as simple as the keyboard or as sophisticated as those used for specialized applications such as voice or retinal recognition. 5 • The Keyboard is the most commonly used input device for entering numeric and alphabetic data into the computer • A wide variety of computers are available: Ergonomic Wireless Specialized Security Flexible Biometric fingerprint reader 6 A pointing device is an input device that allows a user to position the pointer on the screen. The pointer can have several shapes, but the most common is an arrow. You can use the pointing device to select objects, click buttons, icons, menu items and links. 7 The mouse is the most commonly used pointing device for personal computers. It moves around on a flat surface and controls the pointer (arrow) on the computer screen. The mouse fits conveniently in the palm of your hand. There are four types of mice 8 This type of mouse has a ball located on the bottom that rolls on a flat surface as the mouse is moved. Sensors inside the mouse determines the direction and distance of movement. A mouse pad generally is used with a mechanical mouse. 9 This mouse is the same as the mechanical mouse, but uses optical sensors to detect motion of the ball. 10 An optical mouse uses a laser to detect the mouse’s movement. Optical mice have no mechanical moving parts. They respond more quickly and precisely than mechanical and optomechanical mice. 11 A wireless mouse is a battery- powered device that relies on infrared or radio waves to communicate with the computer. 12 You will use the left button for mouse operations. Generally, clicking the right button displays the context window. The type of actions will depend on the program you are currently using. 13 Pointing: placing the on-screen pointer at a designated location Clicking: pressing and releasing the mouse button to select a specific location within a document Dragging: pressing down the mouse button and moving while continuing to hold down the button to highlight a selected portion of text Double-clicking: pressing and releasing the mouse button two times in rapid successions to select a word 14 Triple-clicking: pressing and releasing the mouse button three times in rapid succession to select a paragraph Right-clicking: pressing the right mouse button to display a menu Rotate wheel: rotating wheel on the mouse forward or backward to scroll vertically through a document screen Tilt wheel: pressing the mouse’s rotate wheel right or left to scroll horizontally 15 The trackball is a pointing device that works like a mouse turned upside down, as the ball is on the top of the device. Trackballs You use your thumb or fingers to operate the ball, thus controlling the pointer on the screen. 16 The joystick is also pointing devices mainly used in games. The joystick consists of plastic or metal rod mounted on a base. You can move the rod in any directions. Some joysticks have switches or buttons that can input data in an on/off response. 17 The wheel is a steering- wheel type of pointing device used to simulate driving a vehicle. Most wheels also include foot pedals used for braking and acceleration actions. 18 Pointing Stick A pointing stick is a pressure-sensitive device that looks like a pencil eraser. It is locate on the keyboard, generally between the G, H and B keys. It is moved with the forefinger, while the thumb is used to press related keys. 19 There are a variety of other input devices available, most of which are used for special application. 20 Graphic Tablet, also called a digitizing tablet, is a flat drawing surface on which the user can draw figures or write something freehand. Touch Display Screen is a special screen with pictures or shapes. You use your fingers to “point” to the desired object to make a selection 21 Stylus and digital pen are pen-like writing instruments. These devices allow the user to input information by writing on a PDA or other mobile device or to use the pen as a pointer. 22 Audio Input is the process of inputting sound into the computer. This could include speech, sound effects and music. Audio Input includes microphones, CD/DVD players, radios, and other devices such as electronic keyboards. 23 Voice input is a category of audio input. Voice recognition devices are used to “speak” commands into the computer and to enter text. The computer must have some type of voice recognition software installed. 24 Touchpad is a device commonly used on laptop computers. To move the pointer, you slide your fingertips across the surface of the pad. To imitate the mouse operations, clicking, tap or double-tap the surface of the touchpad. 25 A scanner is a device that can change images into codes for input into the computer. Scanners come in a variety of sizes, shapes and types, including the following: 26 Image Scanners convert images into an electronic form that can be stored in a computer’s memory. The image can then be manipulated. Bar Code Scanners read bar lines that are printed on products in a store. 27 These devices read coded information on the back of credit cards. The magnetic strip on the back of the cards contains the encoded user’s account number. 28 These devices use a light source to read characters, marks, and Optical codes. Scanner The data is converted into digital data. Banks use OCR technology to scan checks. Bluetooth OMR can be used for Scanner testing purposes. 29 The pictures taken with a digital camera are stored digitally and then transferred to the computer’s memory. Digital cameras use a variety of mobile storage media to store the images including: • Flash Memory Card • Memory Stick • USB • Mini-disc 30 Consists of solid-state storage devices. After the pictures are transferred to the computer, they can be viewed quickly and any imperfections can be edited with photo- editing software. 31 Video Input is the process of capturing full-motion images with a type of video camera and then saving the video on a storage medium such as a hard drive, CD or DVD. After the video is saved, you can view and edit it. 32 A digital video (DV) camera records video as digital signals: some cameras also capture still images. Some are just a little larger than a credit card. 33 The PC Video Camera is a type of digital cameras that allows the user to send live images over the Internet, make video telephone calls, and send e-mail messages with video attachments. 34 A Web camera, or Webcam is a real-time camera that displays images through the World Wide Web. The camera may be built into your monitor, or you can attach one an existing monitor. 35 Biometrics is an authentication technique using automated methods of recognizing a person based on a physiological or behavioral characteristics. Biometric devices consist of a reader or scanning device, and software that converts scanned information into a digital format. The scanned information is then compared to a database of stored biometric data. 36 Some of the more common types of recognition are: Fingerprint Face Handwriting Voice 37 Retina (analysis of the capillary vessels located at the back of an eye) Hand Geometry (analysis of the shape of the hand and length of the fingers) Vein (analysis of the pattern of veins on the back of the hand and the wrist) 38 Enrollment: The user enrolls in the system by establishing a baseline measurement for comparison. Submission: The user presents biological proof of his or her identity to the capture system. Verification: The system compares the submitter sample with the stored sample. 39 Privacy and civil liberties advocates ‘s are concerned about the widespread adoption of biometric systems. • Concerns that third parties can access the data without an individual’s consent • Eroding of an individual’s control over the uses of their information 40 Several companies now offer biometric computer keyboards and USB flash drives with fingerprint authentication that can be used for personal applications. 41 Visual Devices uses the synchronized position of light emitting and sensing devices to detect user impact. Virtual Piano Keyboard Virtual computer keyboard 42 The Touch-Sensitive Pad on a portable device, such as an iPod, enables the user to scroll through and adjust the volume, play music, view videos or pictures, and customize settings. 43 As data is entered in the computer and processed, it is stored in RAM (temporary memory).