In this chapter, we delve into the fundamental components that make up a computer system: Hardware. Computer hardware consists of the physical components that make up a computer system. This includes input devices (like keyboards and mice), output devices (such as monitors and printers), and storage devices (including hard drives and SSDs). Peripheral devices, like printers and scanners, expand the functionality of the computer. These devices connect to the computer either via cables (like USB) or wirelessly (using technologies such as Bluetooth and Wi-Fi).
Understanding computer hardware is essential for knowing how computers work and their applications in everyday tasks.
By the end of the lesson, learners must be able to:
Define computer hardware and identify its various components.
Describe different types of ports and connectors used for connecting devices.
Explain the concept of input and distinguish between different types of input data.
List and recognize common input devices used in computing.
Define output and differentiate between various types of output data.
Identify and describe common output devices utilized in computing.
Define storage devices and categorize them based on their functionality.
Demonstrate an understanding of methods for connecting peripherals to a computer system, including both cabled and wireless options.
A computer is composed of two main parts: hardware and software. Hardware refers to all the physical components of a computer, such as the monitor, keyboard, storage devices (like hard drives), graphics card, sound card, and motherboard. Software, on the other hand, consists of instructions that are stored and executed by the hardware.
Hardware can be categorized into several types:
Input Devices
Output Devices
Storage Devices
Ports and Connectors
Ports and Connectors are essential for connecting hardware devices to the computer. Ports enable connections with various hardware like keyboards, mice, and monitors. Devices can connect using cables (wired), Wi-Fi (wireless), or Bluetooth (short-range wireless). See on figure 1, different ports in a computer.
Connectors (plugs) at the end of cables fit into specific ports (sockets) typically located at the back of a computer. Understanding these connections is crucial for setting up and using peripherals effectively. See figure 2 different types of computer connectors.
Figure 1: Ports
Figure 2: Connectors
Different types of ports, common connectors and examples.
Figure 3: ports and connectors
Adapters and Converters
Nearly every peripheral device requires an adapter to communicate effectively with a computer. As technology evolves, the types of ports and devices in computing also change. Instead of replacing your computing devices entirely, adapters and converters provide additional compatibility and functionality.
Common types of adapters include:
HDMI to VGA Adapters: Used to connect devices with HDMI outputs to VGA displays.
HDMI to DVI Adapters: Used to connect devices with HDMI outputs to DVI displays.
These adapters allow users to bridge different types of connectors, ensuring compatibility between various devices and ports without the need for complete hardware replacement. Please watch the video below to learn more about adapters and convertors.
Figure 4: Input devices
Input refers to data or instructions entered into the computer. This can include text, numbers, static or video images, and sound.
Common Input Devices
Keyboards:
Keyboards can be standalone devices, as seen with desktop computers, or integrated into the computer, like with laptops.
Touchscreen Devices:
Devices such as tablets or cell phones use virtual keyboards displayed on the screen.
Mouse:
Traditional mice used to have a ball for movement detection. Modern optical mice use LED technology for tracking movement. Wireless mice connect to computers using infra-red light or Bluetooth.
Pointing Devices:
These devices control the cursor on the computer screen.
Touchpad: A small, pressure-sensitive pad for navigation.
Trackball: A fixed device with a movable ball for control.
Pointing Stick: A pressure-sensitive stick operated by the finger.
Touchscreen: A sensitive screen operated by finger touch or stylus.
Stylus: A pen-like tool used directly on touchscreens.
See the different types of input devices in figure 4.
Figure 5: Output devices
Output refers to data or instructions produced by the computer after processing input. It can be in the form of hardcopy (printed on paper) or softcopy (displayed electronically).
Softcopy: Text or graphics displayed electronically, typically on a monitor.
Hardcopy: Text or graphics printed out on paper.
Common Output Devices
Monitors:
LCD monitors have advantages such as taking up less desk space, producing less heat, and using less electricity.
LED monitors are replacing LCDs as they are even thinner and more energy-efficient.
Monitor size is measured diagonally across the display area.
Images on monitors are formed by pixels (picture elements), with resolution measured in dots per inch (dpi).
Printers:
Inkjet Printers: Spray tiny droplets of ink onto paper to create images.
Laser Printers: Use a drum to magnetize parts, attract toner, and heat the paper to bond toner permanently. They offer higher print quality and faster speeds.
Printer resolution is measured in dpi; higher dpi results in finer print quality.
Comparison:
Inkjet printers are cheaper and better for color printouts.
Laser printers excel in monochrome print quality and efficiency.
Headsets and Speakers:
Speakers: Output audio so users can hear sound from the computer.
Headsets: Worn over the ears for private audio listening.
Fax Machines and Fax Modems:
Fax Machine: Scans and transmits documents over telephone lines to reproduce copies.
Fax Modem: Allows computers to send and receive faxes digitally.
Data Projectors:
Used to project computer monitor images onto larger surfaces like walls.
Types include LCD projectors (use liquid crystal displays) and DLP projectors (use digital light processing).
See the different types of output devices in figure 5.
Storage media are used to save data and information for later use. Storage space is measured in bytes, with common multiples being megabytes (MB) and gigabytes (GB). A storage device allows data to be written to and retrieved from it.
Measuring Capacity
Capacity refers to the amount of data that can be stored on a storage device. It is typically measured in units such as:
Bytes: The smallest unit of digital information.
Kilobytes (KB): Approximately 1,000 bytes.
Megabytes (MB): Approximately 1 million bytes or 1,000 KB.
Gigabytes (GB): Approximately 1 billion bytes or 1,000 MB.
Terabytes (TB): Approximately 1 trillion bytes or 1,000 GB.
The capacity of a storage device determines how much data it can hold. For example, a storage device with a capacity of 500 GB can hold approximately 500 billion bytes of data.
Understanding capacity helps users choose the appropriate storage device based on their needs, whether for personal files, multimedia, or professional applications requiring large data storage capabilities.
When choosing storage devices, consider these three factors:
Capacity: Determines how much data the device can store (measured in GB or TB).
Speed: Determines how quickly data can be written to or read from the device.
Reliability: Indicates how likely the device is to malfunction or fail over time.
Understanding these factors helps in selecting storage devices that meet your needs for storing, accessing, and preserving data.
3. Common storage devices
A peripheral is an external device that connects to a computer, enhancing its functionality. Without peripherals like a mouse or keyboard, a PC cannot operate efficiently.
Peripherals can be connected in two main ways: wired (cabled) or wireless, using interfaces like USB, Bluetooth, or Wi-Fi. These methods allow devices to communicate with the computer and enable users to interact with and control their systems effectively.
In this section, we will explore the various methods used to connect peripherals, ensuring compatibility and efficient operation of computer systems.
Cabled Connections (USB)
Connecting a keyboard with a USB cable involves plugging the USB cable of the peripheral device directly into the computer's USB port. Once connected, the computer will automatically recognize the keyboard, allowing you to start using it immediately.
Wireless Connections (Bluetooth)
To connect a new peripheral using Bluetooth:
Open the Settings menu on your computer.
Navigate to Devices.
In the Bluetooth & other devices section, toggle Bluetooth on.
Click on Add Bluetooth or other device.
Choose Bluetooth from the options.
Power on the peripheral device and ensure it's discoverable.
Select the device from the list shown on your computer.
Click Connect to pair the device.
Once connected, click Done to complete the setup.
Wi-Fi Connections
To connect a new peripheral using Wi-Fi:
Click Start, then navigate to Devices and Printers.
Select Add a printer from the menu.
Follow the instructions in the Add a printer wizard.
Choose Add a network, wireless, or Bluetooth printer option.
Follow the prompts to connect the peripheral device to your Wi-Fi network.
Green computing refers to the environmentally responsible use of computers and related resources. It involves practices aimed at reducing the environmental impact of computing activities, such as minimizing energy consumption, reducing electronic waste, and promoting the use of sustainable materials like recycled paper.
How to practice green computing:
Power Management: Set computers to sleep or hibernate mode when not in use to save energy.
Digital Documentation: Embrace digital documents and emails to reduce printing and paper waste.
Recycling Electronics: Dispose of old computers, peripherals, and printer cartridges responsibly through recycling programs.
Energy-efficient Hardware: Choose energy-efficient devices and components when upgrading or purchasing new equipment.
Cloud Computing: Utilize cloud services for data storage and software applications to reduce the need for on-site hardware and energy consumption.