Week-3.pdf

C S 0 0 1 Input and output Devices 1 I/O devices An input device is any device that allows you to enter data into a computer and C S 0 0 1 interact with it. Output devices take the processed input from a computer and display it in a way that is easy for humans to understand. 2 Input and output Devic...

C S 0 0 1 Input and output Devices 1 I/O devices An input device is any device that allows you to enter data into a computer and C S 0 0 1 interact with it. Output devices take the processed input from a computer and display it in a way that is easy for humans to understand. 2 Input and output Devices Input and output Devices Input Devices An input device is a piece of computer hardware used to provide data and control signals to a computer. It allows users to communicate with and feed data into the computer for processing. Examples include keyboards, mice, scanners, and microphones. C S 0 0 1 Output Devices An output device is a piece of computer hardware that receives data from a computer and then translates that data into another form, such as visual, auditory, or physical form. These devices enable the user to view, hear, or even feel the results of the computer's processes. Examples include monitors, printers, speakers, and headphones. 3 Input and output Devices Input Devices Keyboard: A keyboard is a primary input device used with computers and other digital systems. Components and Layout: C S 0 0 1 Alphanumeric Keys: Include letters (A-Z) and numbers (0-9). Function Keys: Located at the top of the keyboard (F1-F12). Special Keys: Include Shift, Ctrl, Alt, and the Windows key. Navigation Keys: Include arrow keys,Home,End,Page Up, and Down. Modifier Keys: Include keys like Shift, Ctrl, Alt, which modify the function of other keys when pressed simultaneously. 4 Input and output Devices Input Devices Keyboard: Types of Keyboards: C S 0 0 1 Standard Keyboard: The most common type used with desktop computers. Wireless Keyboard: Connects to the device without physical cables, typically using Bluetooth or a wireless receiver. Virtual Keyboard: A software-based keyboard displayed on a touchscreen device. 5 Input and output Devices Input Devices Mouse: A computer mouse is a handheld pointing device that detects twodimensional motion relative to a surface. This physical movement is translated into the motion of a cursor on a display screen. Types of Computer Mice: C S 0 0 1 Wired Mouse: Connects to a computer via a physical wire, typically USB. Wireless Mouse: Connects to the computer without wires, usually via Bluetooth or a wireless USB receiver. Ergonomic Mouse: Designed to reduce muscle strain and decrease discomfort from prolonged use. 6 Input and output Devices Input Devices Scanner: Is a digital device that captures images from photographic prints, posters, magazine pages, and other printed materials. In the context of computers, it refers to a device used to convert a physical image or document into a digital format through a process called scanning. C S 0 0 1 Types of Scanners: Flatbed Scanner: Resembles a small photocopy machine. It has a flat glass surface to place documents. Sheet-fed Scanner: Similar to a flatbed but has a feed where papers are fed one at a time. Handheld Scanner: A manual device that is moved over the document. 7 Input and output Devices Input Devices Microphone: A computer microphone, often referred to simply as a mic, is an input device that captures C S 0 0 1 and converts sound waves (Analog) into an electrical (Digital0 signal, which can then be processed or recorded by a Input computer. Microphones are commonly used for various applications, including voice communication, recording, voice recognition, and more. 8 Input and output Devices Input Devices Digital Camera and Webcam: Both serve as imaging devices, but they are designed for different primary functions and have some distinct characteristics. C S 0 0 1 Webcam: primarily used for video conferencing, live streaming, and other online communication purposes. They often come built into laptops or monitors, but there are also standalone versions available. Digital Camera: primarily designed for photography and videography. They capture high-resolution images and videos for a wide range of professional and personal applications. 9 Input and output Devices Input Devices Touchscreen: is a direct manipulation input device that allows users to interact with a digital C S 0 0 1 display using touch gestures. This means users can control interface elements and execute commands on the screen directly with their fingers or a stylus pen, without the need for a traditional keyboard or mouse. 10 Input and output Devices Output Devices Monitor/Display Screen: A monitor or display screen is an electronic visual display device that presents images, text, and videos to the user. It is one of C S 0 0 1 the primary output devices used with computers, providing a visual representation of the information processed by the computer. Types of Display Technologies: Cathode Ray Tube (CRT): An older technology, CRT monitors use electron guns to illuminate phosphors on the screen. 11 Input and output Devices Output Devices Monitor/Display Screen: Types of Display Technologies: Liquid Crystal Display (LCD): These use liquid crystals and backlights to produce images on the C S 0 0 1 screen. LCDs are thinner and consume less power than CRTs. Light Emitting Diode (LED): A subtype of LCDs but with LED backlighting, resulting in brighter, more vibrant images and better black levels. 12 Input and output Devices Output Devices Monitor/Display Screen: Key Features Resolution: Refers to the number of pixels on the screen. Common resolutions include 1080p (Full HD). C S 0 0 1 Refresh Rate: Measures how many times the screen is redrawn in a second. Common refresh rates are 60Hz, 120Hz, and 144Hz. Response Time: Measures how quickly a pixel can change colors, usually calculated in milliseconds (ms). Lower response times are preferable for fast-paced actions, like gaming. Aspect Ratio: The ratio of the width to the height of the screen. Common aspect ratios are 16:9 and 4:3. 13 Input and output Devices Output Devices Printer: An external peripheral device responsible for producing a permanent human-readable representation of graphics or text on paper. Types of Printers: C S 0 0 1 Dot Matrix Printer: Uses a matrix of small pins to strike against an ink ribbon, transferring ink onto paper. Produces characters and graphics by patterns of dots. Commonly used for multi-part forms as they can print through several layers of paper. 14 Input and output Devices Output Devices Types of Printers: Inkjet Printer: C S 0 0 1 Uses liquid ink sprayed through tiny nozzles onto the paper. Capable of producing high-quality, color outputs. Commonly used in homes and small offices. Laser Printer: Uses a laser beam to produce an image on a drum. The image is then transferred from the drum to paper through an electrostatic process. Known for fast printing speeds and high-quality outputs. Often used in larger office settings. 15 Input and output Devices Output Devices Printer: Key Features: C S 0 0 1 Resolution: Measured in dots per inch (DPI), it indicates the print quality. Higher DPI values mean finer, clearer prints. Speed: Indicates how many pages a printer can produce in one minute (pages per minute, or PPM). Connectivity: Printers can connect to devices via USB, Ethernet, Wi-Fi, or even Bluetooth. 16 Input and output Devices Output Devices Speaker: the computer speaker system takes the digital audio data from the computer, C S 0 0 1 converts it into an analog signal using the DAC (Digital-to-Analog Converter) in the Output sound card, amplifies the signal, and then uses that signal to produce sound waves through the physical movement of its drivers. 17 Input and output Devices Input and output Devices. Combined Input/Output Devices Modem: A modem, which stands for "modulator- demodulator," is a combined input/output device C S 0 0 1 that allows computers to communicate with each other over telephone lines or other transmission mediums. The primary function of a modem is to convert digital data from a computer into a format suitable for transmission over analog communication lines, such as a telephone line. 18 Input and output Devices Input and output Devices. Combined Input/Output Devices Modem: Modulation: the modem converts (or modulates) the digital signal from the C S 0 0 1 computer into an analog signal that can be transmitted over telephone lines. Demodulation: When receiving data, the modem converts (or demodulates) the incoming analog signal into a digital signal that the computer can understand and process. 19 Input and output Devices Input and output Devices. Combined Input/Output Devices Network Card: Input Functionality: The NIC receives data packets from the network and C S 0 0 1 sends them to the computer's processor for further action. Output Functionality: It also takes data from the computer's processor and sends it out to the network. 20 Input and output Devices Input and output Devices. Combined Input/Output Devices Touchscreen Monitor: Input Functionality: When you touch or swipe the screen, it registers that touch as an input. C S 0 0 1 This allows users to interact with software applications, enter data. Output Functionality: The touchscreen also displays visual information (output) to the user, such as graphics, text, and videos. 21