Computer system
A computer system is a set of integrated devices that input, output, process, and store data and information. Computer systems are currently built around at least one digital processing device. There are five main hardware components in a computer system: Input, Processing, Storage, Output and Communication devices.
Components of computer system:
- Input Unit
A computer will only respond when a command is given to the device. These commands can be given using the input unit or the input devices. For example: Using a keyboard The data entered can be in the form of numbers, alphabet, images, etc. We enter the information using an input device, the processing units convert it into computer understandable languages and then the final output is received by a human-understandable language.
Keyboard:
A computer keyboard is an input device used to enter characters and functions into the computer system by pressing keys. It is the primary device used to enter input or text. A keyboard typically contains keys for individual letters, numbers and special characters, as well as keys for specific functions.
Mouse:
A pointing device that allows users to interact with graphical user interfaces by moving a cursor on the screen and clicking on objects is called mouse or A mouse is a small device that a computer user pushes across a desk surface in order to point to a place on a display screen and to select one or more actions to take from that position.
Touchpad:
A touchpad is a flat, touch-sensitive device that replaces the mouse on laptops and netbooks, allowing you to control the cursor and perform other actions. Touchpads contain a small pointing device with touch-sensitive areas that the user drags and taps their finger over.
Touchscreen:
A touchscreen is a type of display that can detect touch input from a user. It consists of both an input device and an output device. The touch panel is typically layered on the top of the electronic visual display of a device.
Trackball:
A trackball is a pointing device consisting of a ball held by a socket containing sensors to detect a rotation of the ball about two axes—like an upside-down ball mouse with an exposed protruding ball.
Graphics Tablet:
A graphics tablet is an optional electronic input device for computers, generally used by architects, engineers, artists, and others who want to correctly measure pictures
Scanner:
A scanner is a device that allows you to digitize physical documents, images, or even objects, and convert them into a digital format that can be viewed, edited, and stored on a computer. It’s like a digital photocopier that captures the content of a document or image and saves it as a file.
Webcam:
A webcam is a digital camera that captures video and audio data and transmits it in real-time over the internet. It is commonly used for video conferencing, live streaming, online meetings, and recording videos.
Microphone:
A microphone is a device that converts sound waves into an electrical signal. It allows you to capture audio and transmit it to various devices, such as computers, amplifiers, or recording equipment.
Barcode Reader:
A barcode reader is a handheld input device that collects the information from the printed design to decode the data in the meaningful information in the system. A barcode reader uses different types of technologies to differentiate the process of scanning in the various types of optical scanners.
Biometric Scanner:
Biometrics scanners are hardware used to capture the biometric for verification of identity. These scans match against the saved database to approve or deny access to the system. In other words, biometric security means your body becomes the “key” to unlock your access. Such as finger prints, face locks, etc.
Gamepad/Joystick:
Input devices used for gaming, with buttons, triggers, and directional controls for navigating virtual environments and controlling characters. A gamepad, game controller, joypad, or video game controller is a peripheral device designed to connect to a computer or console gaming system. It has multiple buttons and may have one or two mini.
Motion Sensor:
A motion sensor, also known as a motion detector, is a device that detects movement within its field of view or detection range. It typically works by sensing changes in infrared radiation, ultrasonic waves, or microwaves caused by moving objects. Motion sensors are commonly used in security systems, lighting systems, and home automation to trigger actions such as turning on lights, sounding alarms, or activating cameras when motion is detected.
Light Pen:
A light pen is an input device that looks like a pen or stylus but operates differently. Instead of writing on paper or a tablet, a light pen is used to interact directly with a computer screen or monitor. It works by detecting the light emitted by the screen’s phosphor dots or LCD pixels when the pen’s tip touches the screen. Light pens were popular in early computer systems for tasks such as drawing, selecting options, or entering data directly on the screen.
Gesture Recognition Device:
A gesture recognition device is a technology that interprets human gestures or movements to control electronic devices or interact with digital interfaces. These devices use sensors such as cameras, depth sensors, or accelerometers to capture and analyze the user’s movements. Gesture recognition technology can be found in various applications, including gaming consoles, smartphones, virtual reality systems, and smart TVs
Remote Control:
A remote control is a handheld device used to operate electronic devices from a distance, typically via infrared (IR) or radio frequency (RF) signals. Remote controls are commonly used with televisions, DVD players, stereo systems, air conditioners, and other appliances. They feature buttons or keys that correspond to specific functions or commands, allowing users to adjust settings, change channels, play media, and perform other actions without needing to be directly in front of the device.
Output Unit
When we command a computer to perform a task, it reverts for the action performed and gives us a result. This result is called output. There are various output devices connected to the computer. The most basic of which is a monitor. Whatever we write using a keyboard or click using a mouse, is all displayed on the monitor.
Softcopy output device:
A soft copy output device refers to any device that produces output in digital or electronic form, which can be viewed on a screen or stored electronically. Here are some examples:
Monitor/Display:
The most common soft copy output device, which displays text, graphics, and multimedia content on a screen.
Projector:
Used to display images, videos, or presentations on a large screen or wall.
Printer (Digital):
Some modern printers can produce soft copy outputs by scanning documents and saving them as digital files.
E-book Reader:
Devices designed for reading electronic books and documents, such as e-readers or tablets.
Digital Camera:
Captures photographs and videos in digital format, which can be viewed on screens or stored electronically.
Smartphone/Tablet:
Mobile devices with screens that display various types of content, including text, images, videos, and applications.
Digital Audio Player:
Devices that play digital audio files, such as MP3 players or smartphones, outputting sound through headphones or speakers.
Digital Signage Display:
Large screens used for displaying advertisements, information, or multimedia content in public spaces.
Digital Photo Frame:
Displays digital photographs in slideshow format on a screen.
Hardcopy output device
A hardcopy output device is a device that produces a physical, tangible copy of digital data. Here are some common examples:
Printer:
Printers are perhaps the most well-known hardcopy output devices. They come in various types, including inkjet printers, laser printers, and dot matrix printers, and they produce printed documents on paper.
Plotter:
Plotters are used to produce large-scale, high-quality graphics such as engineering drawings, architectural plans, and maps. They use pens or markers to draw precise lines on paper or other materials.
Photocopier:
Photocopiers create duplicate copies of documents by scanning the original and printing it onto another sheet of paper.
3D Printer:
Unlike traditional printers, 3D printers create three-dimensional objects by depositing successive layers of material, such as plastic, resin, or metal. They are commonly used in prototyping, manufacturing, and rapid prototyping applications.
Fax Machine:
While less common today, fax machines are still used in some industries to transmit documents over telephone lines. They convert digital documents into analog signals that can be transmitted and printed on the receiving end.
Thermal Printer:
These printers use heat to produce images on special thermal paper. They are often used in point-of-sale systems, label printing, and certain types of receipts.
Label Printer:
Label printers are specialized printers used to print labels for various applications such as shipping, barcode labels, product labeling, and address labels.
Different between impact printer and non-impact printer
| Impact printer | Non-impact printer |
| It produce character or graphics on a piece of paper by using striking mechanism. | It printer produces characters and graphics on a piece of paper without using striking mechanism. |
| It produce noise because of striking of print hammer on paper. | It works silently without producing noise. |
| Its printing quality is lower. | Its printing quality is better. |
| It uses inked ribbon printing. | It uses toner, cartridge for printing. |
| Electro-mechanical devices are used for printing. | No electro-mechanical devices are used for printing. |
| Its printing speed is slower. | Its printing speed is faster. |
| Example: Dot matrix, Daisy wheel etc. | Example: Laser printing, Inkjet printing, etc. |
Processing unit:
After receiving data and commands from users, a computer system has to process it according to the instruction.
The components of processing unit are listed below:
Memory Unit
When we enter the data into the computer using an input device, the entered information immediately gets saved in the memory unit of the Central Processing Unit (CPU). Because of the presence of some existing programming, the Memory Unit transmits the data further to the other parts of the CPU.
Control Unit
This is the core unit which manages the entire functioning of the computer device. It is one of the most essential components of the computer system. The Control Unit collects the data entered using the input unit, leads it on for processing and once that is done, receives the output and presents it to the user. It can be said to the centre of all processing actions taking place inside a computer device.
Arithmetic and logic unit
ALU is a part of CPU which performs arithmetic and logical operations on the data. The arithmetic operation can be addition, subtraction, multiplication and division and also the logical operator such as less than, greater than, smaller than, AND, OR, NOT.
Microprocessor
A microprocessor is an integrated circuit (IC) that serves as the central processing unit (CPU) of a computer. It contains the arithmetic logic unit (ALU), control unit, and registers. Here’s a breakdown of its components:
Arithmetic Logic Unit (ALU):
The ALU performs arithmetic and logic operations on the data that is fed into it. Arithmetic operations include addition, subtraction, multiplication, and division, while logical operations include AND, OR, NOT, and XOR.
Control Unit (CU):
The control unit manages the execution of instructions by decoding them and coordinating the operations of the other components of the microprocessor. It fetches instructions from memory, decodes them, and then executes them by sending appropriate signals to the ALU, registers, and other parts of the CPU.
Registers:
Registers are small, high-speed storage units within the CPU used to store data temporarily during processing. Some common types of registers include:
Program Counter (PC):
Stores the memory address of the next instruction to be fetched and executed.
Instruction Register (IR):
Holds the current instruction being executed.
Accumulator (ACC):
Stores the results of arithmetic and logic operations performed by the ALU.
Memory Address Register (MAR):
Holds the memory address of data that needs to be fetched from or stored into memory.
Memory Data Register (MDR):
Contains the actual data that is being fetched from or stored into memory.
General-Purpose Registers (GPRs):
Used for various purposes during program execution, such as storing operands and intermediate results.
Clock:
The clock provides timing signals to synchronize the operations of the microprocessor. It generates regular pulses, and each pulse represents a fixed unit of time, known as a clock cycle. The speed of the clock is measured in hertz (Hz), and it determines how fast the microprocessor can execute instructions.
Cache Memory:
Some microprocessors include cache memory, which is a small but fast memory unit used to temporarily store frequently accessed instructions and data. This helps improve the overall performance of the CPU by reducing the time taken to access data from the main memory.
Word length:
Word length refers to the number of bits that can be processed simultaneously by the CPU. It determines the size of data that the CPU can handle in a single operation. The word length has implications for the CPU’s performance, memory addressing capabilities, and the size of data it can handle efficiently. A larger word length generally allows for faster processing and larger memory addressing capacity, but it also increases the complexity and cost of the microprocessor.