Lesson 2: Fundamentals of a Computer System

Lesson 2: Fundamentals of a computer system What is a computer?A computer is an electronic device that manipulates information or data. What does a computer does?They are changing the way we live our life. Characteristics of a computer Speed Accuracy Versatility Efficiency Storing and retrieving Speed -> A computer can perform millions of calculations in a second. Accuracy -> Computers perform all jobs with 100% accuracy. Versatility->Computer can be used to perform various tasks at the same time. Efficiency-> A computer can work continuously without getting tired. Storing and Retrieving->A computer can store billions of bytes of information. Computer Classification According to physical size According to technology Classification Classification according to physical size Super computers Super computers with excellent storage capacity, are considered the fastest computer in data processing and handling. They are big and have multiple CPUs for faster data and information access and processing. Example-IBM Seirra, Sunway taihu light Mainframe computers These computers are small in size compared to super computer. Fast and can store a massive amount of data and information. They have extremely impressive data processing and handling abilities, and number of users can connect to them quickly for better sharing and functionality. Example-Z890,hitachi Z800 Mini computers Are considerably smaller in size when compared to super computers and mainframe computers. Mini computer consist of more than 1 CPU making then faster than micro computers and costlier than microcomputers. Micro computers Are compact in shape and size and use a micro processor , processor, or CPU for processing and calculations. They are comparatively relatively smaller than other computers. Classification according to technology Analog computers Analog computers are computers that operate on continuous data through measuring physical quantities like temperature, voltage, speed, current, pressure. Example-Speedometer, thermometer Digital computers Works on discrete data or discontinuous data. It accepts data as digits or number and processors it with programs stored in the memory to produce desired output. Digital computer works on a binary system where 0 represents off and 1 represents on. It is based on digital signals. Example-Smart phones, laptops Hybrid computers These combines the features of both analog and digital computers. It can perform the tasks of both analog and digital computers. The hybrid computer can convert the analog signal into digital signal and digital signal into the analog signal. Functions of a computer system Computers are incredibly versatile machines that can perform a wide range of tasks. These tasks are made possible by the four basic functions of a computer. Input, Process, output and storage. Each of the functions are essential for the computer to operate correctly and perform useful tasks. Whether you're writing an email, playing a video game, or managing spreadsheets ,these fundamental functions enable the processing and output of data that makes computers invaluable in our daily lives. Components of computer architecture Central processing Unit The Central Processing Unit (CPU) is like the "brain" of the computer. It follows instructions, does calculations, and handles data. Its design affects things like how fast it works, how it processes instructions, and how it stores quick-access data, all of which influence the computer's speed and performance. Memory hierarchy This includes different types of memory, like cache memory, random access memory (RAM), and storage devices. The way memory is arranged helps speed up data access, as data moves between different types of memory based on how close they are to the CPU and how often they are needed. Input/Output system The I/O system enables communication between the computer and external devices, such as keyboards, monitors, and storage devices. It involves designing efficient data transfer mechanisms to ensure smooth interaction and data exchange. Storage architecture This deals with how data is stored and retrieved from storage devices like hard drives, solid-state drives (SSDs), and optical drives. Efficient storage architectures ensure data integrity, availability, and fast access times. Instruction pipelining Modern CPUs employ pipelining, a technique that breaks down instruction execution into multiple stages. This allows the CPU to process multiple instructions simultaneously, resulting in improved throughput. Parallel processing This involves dividing a task into smaller subtasks and executing them concurrently, often on multiple cores or processors. Parallel processing significantly accelerates computations, making it key to tasks like simulations, video rendering, and machine learning. Basic physical components of a computer system. Input Devices Keyboard-The keyboard is a basic input device that is used to enter data into a computer or any other electronic device by pressing keys. It has different sets of keys for letters, numbers, characters, and functions. Keyboards are connected to a computer through USB or a Bluetooth device for wireless communication. Pointing Devices Mouse-The mouse is a hand-held input device which is used to move cursor or pointer across the screen. It is designed to be used on a flat surface and generally has left and right button and a scroll wheel between them. Laptop computers come with a touchpad that works as a mouse. It lets you control the movement of cursor or pointer by moving your finger over the touchpad. Some mouse comes with integrated features such as extra buttons to perform different buttons. Touch screen-It is the display screen of a device such as a smartphone, tablet, etc., that allows users to interact or provide inputs to the device by using their finger. Today, most of the electronic devices come with touchscreen as an alternative to a mouse for navigating a graphical user interface. For example, by touching, you can unlock your phone, open emails, open files, play videos, etc. Besides this, it is used in lots of devices such as Camera, Car GPS, Fitness machine, etc. Joystick-A joystick is also a pointing input device like a mouse. It is made up of a stick with a spherical base. The base is fitted in a socket that allows free movement of the stick. The movement of stick controls the cursor or pointer on the screen. Lightpen-A light pen is a computer input device that looks like a pen. The tip of the light pen contains a light-sensitive detector that enables the user to point to or select objects on the display screen. Its light sensitive tip detects the object location and sends the corresponding signals to the CPU. It is not compatible with LCD screens, so it is not in use today. Imaging and video input devices Digital camera-It is a digital device as it captures images and records videos digitally and then stores them on a memory card. It is provided with an image sensor chip to capture images, as opposed to film used by traditional cameras. Besides this, a camera that is connected to your computer can also be called a digital camera. Webcam-It is a digital device as it captures images and records videos digitally and then stores them on a memory card. It is provided with an image sensor chip to capture images, as opposed to film used by traditional cameras. Besides this, a camera that is connected to your computer can also be called a digital camera. CCTV-Cameras, the central components of CCTV systems, capture visual information from the environment, transforming it into electronic data. This captured data acts as valuable input, facilitating real-time monitoring, event recording, and the potential for post-incident analysis. Scanners Flatbed scanners-It has a glass pane and a moving optical CIS or CCD array. The light illuminates the pane, and then the image is placed on the glass pane. The light moves across the glass pane and scans the document and thus produces its digital copy. You will need a transparency adapter while scanning transparent slides. Barcode reader-It is a small manual scanning device which is held by hand and is rolled over a flat image that is to be scanned. The drawback in using this device is that the hand should be steady while scanning; otherwise, it may distort the image. One of the commonly used handheld scanners is the barcode scanner which you would have seen in shopping stores. Magnetic Ink character recognition-Magnetic ink character recognition (MICR) is a technology that uses magnetic ink to print characters on documents so that machines can read and process them. It's commonly used by banks to process checks. Optical Character recognition-Optical Character Recognition (OCR) is the process that converts an image of text into a machine-readable text format. For example, if you scan a form or a receipt, your computer saves the scan as an image file. You cannot use a text editor to edit, search, or count the words in the image file. However, you can use OCR to convert the image into a text document with its contents stored as text data. Optical Mark recognition-The full form of OMR is Optical Mark Recognition. OMR acknowledges human-created marks on a specially printed paper or journal used in experiments, surveys, etc. It is widely used where a huge number of candidates apply and to evaluate data with consistency and immediate effect. OMR sheet can be read using the OMR reader. Automated Teller Machine-ATMS, or automated teller machines, are banking outlets where you can withdraw cash without going into a branch of their bank. Some ATMs only dispense cash, while others allow transactions such as check deposits or balance transfers 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. Output devices Softcopy Hardcopy Sound 1)Softcopy-A soft copy is a file stored online or in an electronic medium involving no physical space. The digital documents can be read without having to print anything out. A digital version of a physical object such as a printed book contains both the electronic text and any accompanying images. Monitor/screen Most people use computer monitors daily at work and at home. And while these come in a variety of shapes, designs, and colors, they can also be broadly categorized into three types. Cathode Ray Tube monitor These monitors employ CRT technology, which was used most commonly in the manufacturing of television screens. With these monitors, a stream of intense high energy electrons is used to form images on a fluorescent screen. A cathode ray tube is basically a vacuum tube containing an electron gun at one end and a fluorescent screen at another end. Liquid crystal display -LCD The LCD monitor incorporates one of the most advanced technologies available today. Typically, it consists of a layer of color or monochrome pixels arranged schematically between a couple of transparent electrodes and two polarizing filters. Optical effect is made possible by polarizing the light in varied amounts and making it pass through the liquid crystal layer. Light Emitting Diode-LED LED monitors are the latest types of monitors on the market today. These are flat panel, or slightly curved displays which make use of light-emitting diodes for back-lighting, instead of cold cathode fluorescent (CCFL) back-lighting used in LCDs. LED monitors are said to use much lesser power than CRT and LCD and are considered far more environmentally friendly. Multimedia Projector As their name suggests, multimedia projectors allow you to connect to various external devices like DVD players, computers, or laptops and support WiFi and Bluetooth for wireless streaming and screen mirroring to display various content. 2) Hard Copy- A hard copy is a printed form of a digital document file from a computer on paper or any other material that may be transparent. The output prints on paper in a hard copy- thus, sometimes referred to as a permanent copy. It may be a photograph, text, drawing, or other types of printable files. Printers Non-Impact PrintersImpact Printers Dot-matrix printer Line printer Laser Printer Bubble printer/Ink jet printer Impact Printers Creates immediate contact between the ink ribbons and paper. They can be noisy yet are very popular. Impact printers have mechanical components that allow printing. Example 1-Dot Matrix printer A dot matrix printer has a print head through which the tips of nine wires project, forming a vertical column of dots. As the print head scans a page, an electronic mechanism pushes the wires out with precision timing. The wire tips strike a ribbon which touches the paper, producing horizontal patterns of dots that form letters, numerals, lines and other characters. Example 2-Line printer Line printer is an impact printer. it is very fast printer. It prints a complete line of characters at a time. The printing speed of line printer is measured in lines per minute (lpm). It is upto 3000 lines per minute. Line printers are normally used with mainframe and mini computers. Non-Impact Printers Non-impact printers create pictures, characters, and figures without any uninterrupted contact between the printing device and the paper. Example 1- Laser printer Laser stands for Light Amplification by Simulated Emission of Radiation. A laser printer is the fastest and hight quality non-impact printer. It works like a photocopier. The laser printer transfers the image of output on paper using LASER technology and toner. Toner is an ink powder. It is used in laser printers and photocopiers also. Example 2- Bubble/Ink jet printer Ink-jet printer is type of non-impact printer. It creates output on paper by spraying tiny drops of liquid ink. Inkjet printer has print-head that can spray very fine drops of ink. It consists of print cartridge filled with liquid ink and has small nozzles in form of matrix. Example 3- Thermal printers Thermal printer is another type of non-impact printer. It can only print output on a special heat sensitive waxy paper. The image if the output is created on the waxy paper by burning dots on it. For coloured output, coloured waxy sheets are used. Example 4- Plotter Plotters are used to print graphical output on paper. It interprets computer commands and makes line drawings on paper using multicolored automated pens. It is capable of producing graphs, drawings, charts, maps etc. Computer speed-Clock speed or clock rate is the CPU’s operating speed. This tells the number of operations it performs in one second. Previously this was the most important measurement of a CPU’s performance. Computer Memory Primary memory RAM-Any system process that has to be executed is put into RAM, where it is processed by the CPU according to the program’s instructions. If we click on an application like Browser, the Operating System will first load browser code into RAM, following which the CPU will execute and open the Browser. ROM-Any data that does not need to be changed is saved in ROM. The ROM contains both programmes that run when the system boots up (known as a bootstrap programme that initialises the OS) and data such as the algorithm that the OS requires. Nothing can be tampered with or modified in ROM. Cache-Cache memory refers to high-speed memory. It is small but faster than RAM (the main memory). The CPU can access the cache comparatively more quickly than its primary memory. Thus, we use it to synchronize with a highspeed CPU and also to improve its overall performance. Secondary memory Magnetic media devices Magnetic storage media and devices store data in the form of tiny magnetised dots. These dots are created, read and erased using magnetic fields created by very tiny electromagnets. Example 1-Hard Disk drive Hard-drives have a very large storage capacity (up to 1TB). They can be used to store vast amounts of data. Hard-drives are random access devices and can be used to store all types of films, including huge files such as movies. Data access speeds are very fast. Components Platter-The platter is a thin, circular disk where data is physically stored. Modern HDDs typically have multiple platters stacked on top of each other. Spindle-The spindle holds the platters in place and rotates them at high speeds. Head-The read/write head is a small, magnetically charged component that moves across the surface of the platters to either read data stored on the platters or write new data to them. Actuator arm-The actuator arm holds the read/write heads and moves them back and forth across the platters. Power connector-The power connector is where the hard drive receives electrical power from the computer’s power supply. IDE Connnector-Transmits data to the platter. Actuator- The actuator is an electromechanical device that controls the movement of the actuator arm. Example 2-Magnetic Tape Magnetic Tape is a type of storage medium that consists of a thin plastic strip with a magnetic coating, allowing data to be stored sequentially. It was commonly used in early computing systems and is still used today for data backup due to its cost-effectiveness. Optical media devices Optical storage devices save data as patterns of dots that can be read using light. A laser beam is the usual light source. The data on the storage medium is read by bouncing the laser beam off the surface of the medium. If the beam hits a dot it is reflected back differently to how it would be if there were no dot. This difference can be detected, so the data can be read. Solid State Drives The term ‘solid-state’ essentially means ‘no moving parts’. Solid-state storage devices are based on electronic circuits with no moving parts (no reels of tape, no spinning discs, no laser beams, etc.) Example 1-USB flash drive Flash are non-volatile solid state storage devices which use NAND flash memories to store data (millions of transistors). refers to the USB connection that allows users to plug the device into the USB port of a computer. USB Example 2-Memory card Many of our digital devices (cameras, mobile phones, MP3 players, etc.) require compact, non-volatile data storage. Flash memory cards provide this and come in a variety of shapes and sizes. One of the most common formats used by digital cameras is the SD Card. The cards store the digital images taken by the camera. Computer ports A computer port is a piece of hardware that allows a computer to connect to other devices, including accessories, peripheral devices, and other computers. Ports are standard yet versatile component found on most modern computer systems. PS/2 port PS/2 connectors are used for connecting the keyboard and mouse. PS/2 mouse connector and port is usually green in colour. PS/2 for the keyboard is usually purple in colour. USB port USB is the short form for universal serial bus. USB ports and connectors allow the transfer of data to and from digital devices. Many digital cameras and memory card readers connect to the USB port on a computer. Parallel port In contrast to the serial port, parallel ports perform a parallel communication interface. Moreover, it can transfer multiple bits at a time. Besides they also connect devices like printers and scanners. We can also call them printer port. Furthermore, they contain 25 pins, and the speed of data travel is 150-kilo bits per second. HDMI port The full form of HDMI is the High Definition Multimedia Interface. It is an alldigital audio-video interface that transmits information to a computer monitor, video projector, digital television and so on, in uncompressed mode. When you use an HDMI cable, it takes this full-quality video from one device, like a gaming console or DVD player, and shows it on your TV without losing any details. RJ45 port An RJ45 port is primarily used to establish a wired connection between devices on a local area network (LAN) for internet access, file sharing, and other network communications, essentially functioning as the physical interface for Ethernet connectivity, allowing you to connect devices like computers, routers, and switches using an Ethernet cable. Audio ports/Jacks Audio ports link computers with speakers, headphones, and other external output devices. Audio ports can handle analog or digital data, depending on the type of port and the connected device. Display ports connect computers with highresolution digital displays. Video port-Video Graphics Adapter The VGA connector is crucial for connecting video devices like monitors and projectors. It features a 15-pin arrangement in three rows of five, which allows for the transmission of analog video signals. Serial port A serial port is a physical communication interface that enables the transfer of data between devices, such as a computer and a modem or a printer. It transmits data serially, which means that the bits of data are sent one after the other over a single wire. Data Communication Basic components required for data communication Sender: The device or source that originates the data to be transmitted, like a computer sending an email. Receiver: The device that receives the transmitted data, like the recipient's email server. Transmission Medium: The physical pathway through which the data travels, including options like wired cables (copper, fiber optic) or wireless signals (radio waves). Data Transmission modes Simplex mode In this mode, we have unidirectional communication- meaning it’s a one-way street. Out of the two connecting devices, only one is capable of transmission- the other one is only capable of receiving. The simplex mode can always utilize a channel’s entire capacity for sending the data in a single direction. Half-duplex mode In this mode, every station can both- receive and transmit data- but not at the very same moment. When one of the devices sends information, the other one can only then receive it. It also happens vice versa because the transmission is not unidirectional. The half-duplex mode comes into play in those cases where we don’t need the transmission in both directions at the same moment. Full duplex mode In this mode, both the stations have the ability to both receive and transmit data simultaneously. The signals that go in one direction in a Full-Duplex mode share the link’s capacity with the signals that go in the other direction. The Full-Duplex communication mode comes into play when one requires a continuous connection in both directions all the time. However, it needs to divide the channel’s capacity between both these directions. Data Transmission media Guided/Wired Guided media is a type of transmission media in computer networks which is also known as wired or bounded media. These transmission media consist of wires through which the data is transferred. Guided media is a physical link between transmitter and recipient devices. Signals are directed in a narrow pathway using physical links. These media types are used for shorter distances since physical limitation limits the signal that flows through these transmission media. Example 1-Twisted pair Twisted pair cables are like two friends holding hands and spinning around to block out noise! In computer networks, they are made of two insulated wires twisted together, which helps them send information without getting disturbed by other signals. These cables are wrapped in a protective cover to keep them safe. Twisting them helps reduce unwanted signals, like when you cover your ears to block out loud noises. That way, the information travels smoothly without interference, making them the most popular cables for connecting computers and the internet. Unshielded Twisted pair (UTP) Unshielded twisted pair (UTP) cables are like two copper spaghetti noodles twisted together to help messages travel without getting mixed up! These special wires don’t need any extra covering to block out noise—they do it all by twisting around each other. They are super easy to use, don’t cost much, and help computers and the internet talk to each other really fast. That’s why they’re one of the most popular types of cables for networks. Shielded Twisted Pair Shielded twisted pair (STP) cables are like superheroes with an extra layer of armor! They have a special foil shield around them that blocks outside noise, keeping the messages inside clear and fast. Because of this extra protection, they can send data even quicker than regular twisted cables. These special cables are used in super-fast internet connections and telephone lines to make sure voices and data travel smoothly without getting mixed up. Example 2-Coaxial cable Coaxial cables are like special tunnels for information! Imagine a thick wire with different layers, just like a straw inside another straw. Inside, there’s a main wire that carries signals, and around it, there’s a protective layer to keep the signals safe from outside noise. This helps TV, internet, and telephone signals travel fast and clearly without getting mixed up. Coaxial cables are strong and work really well for connecting homes to the internet and cable TV. Example 3-Fiber Optics Cable Fiber optic cables are like magic light tunnels that send information super fast! Instead of using metal wires, they have tiny glass or plastic strands inside. These strands carry data using light, just like a flashlight shining through a clear tube. Because they use light, fiber optic cables are much faster and can send messages really far without losing quality. That’s why they are used for high-speed internet, phone calls, and even in hospitals and space missions. Unguided/Wireless media Wireless media is like sending secret messages through the air! Instead of using wires, it sends signals using invisible waves, just like magic. It works over long distances, letting us use Wi-Fi, mobile phones, and satellite connections without plugging in any cables. The messages travel from a sender to a receiver, like how a radio or a TV gets signals from far away. But since the messages are in the air, they need extra protection to keep them safe from others trying to listen in. Example 1-Radio waves Radio waves are like invisible sound waves that travel all around us! They spread in every direction, just like when you shout and people all around can hear you. These waves help send messages from one place to many receivers, like how radios, TVs, and Wi-Fi work. They can travel through walls and buildings, so we can hear music on the radio even inside our homes! But sometimes, if two signals have the same wave pattern, they can get mixed up, just like when two people talk at the same time, making it hard to understand. Example 2-Microwaves Microwaves are special invisible waves that need a clear path to travel, just like when you shine a flashlight in a straight line. The sender and receiver antennas must be lined up perfectly, which is why this is called line-of-sight transmission. These waves are used for short distances, like sending TV signals or phone calls. Their strength depends on how tall the antenna is—the taller the tower, the farther the signal can go! Microwaves help us communicate quickly, but if something blocks the path, the signal can get weak or lost. Example 3-Infrared Infrared waves are like invisible beams of light that can send information, but only for short distances. Unlike radio waves, they can't go through walls or obstacles, so they stay in one room. They work in things like TV remotes, where you press a button, and the TV gets the signal. Infrared waves are super fast because they can carry a lot of data, and since they don’t spread everywhere, they are safer and don’t get mixed up with other signals easily. Computer network devices Network Interface Card(NIC) A Network Interface Card (NIC) is like a special key that helps a computer talk to other computers on a network! It connects the computer to the internet or other devices, making sure data is sent and received properly. A long time ago, NICs were separate cards plugged into the computer, but now they are built right into most computers. There are different types, like wired NICs that use cables (Ethernet), wireless NICs for Wi-Fi, and fiber optic NICs for super-fast connections. Each NIC has important parts, like a tiny brain (controller) to handle data, a plug for cables, and a special ID called a MAC address, so the network knows who’s who. Switch/Hub A switch in networking is like a smart helper that makes sure messages go to the right places! Imagine a big room full of computers, and each computer wants to send a message to another. The switch is like a traffic controller that looks at each message and sends it to the right computer. It helps all the computers in the room talk to each other without getting in the way or mixing up the messages. Instead of shouting out loud to everyone, the switch makes sure the message only goes to the computer it’s meant for. Wireless Fidelity-( WiFi ) Wi-Fi is like an invisible bridge that helps your devices, like phones, tablets, and computers, connect to the internet without any wires! It uses special waves to send signals through the air, just like a radio sending music to a speaker. When you're at home, school, or a cafe, the Wi-Fi lets you browse the web, watch videos, and play games, all without needing to plug anything in. It's like a magical, invisible web that keeps you connected to everything online. Router A router is like a traffic manager for the internet! It helps direct the flow of data, like making sure cars go the right way on different roads. Routers use special addresses called IP addresses to know where to send data, like sending a letter to the correct house. They also help keep things safe by checking the data before it passes through, like a guard at the gate. Routers make sure everything on the network moves smoothly and doesn’t get stuck or lost. Modem A modem is like a translator for your computer! When you send data, like a message or a video, your computer talks in a digital language. But the internet or cable lines only understand an analog language, so the modem changes the digital signals into analog ones so they can travel. When the data comes back, the modem changes it back to digital so your computer can understand it. It helps your computer talk to the internet through telephone or cable lines. Firewall A firewall is like a security guard for your computer or network! It checks all the data that tries to come in or go out, making sure only safe and allowed information passes through. It follows special rules to decide what’s okay and what’s not, just like how a guard decides who can enter a building. Firewalls can also keep track of what’s happening, like making notes in a notebook, to make sure nothing bad or suspicious gets in. This helps keep your network safe and protected from any dangers. Client/Server network A client/server network is a computing model in which multiple client devices, such as computers or smartphones, connect to a central server to access resources, applications, or data. The server manages network resources, processes requests from clients, and ensures security and data integrity. Clients rely on the server for services like file storage, database access, or web hosting, while the server operates continuously to handle multiple client requests simultaneously. This model is widely used in businesses, websites, and cloud computing, offering centralized control, scalability, and efficient resource management. Types of computer network Local Area Network(LAN) A Local Area Network (LAN) is a network that connects computers and devices within a small area, like a home, school, or office. It allows devices to share files, printers, and internet connections. LANs use cables (like Ethernet) or Wi-Fi to link devices, making communication fast and efficient. Since LANs cover a limited area, they are secure and easy to manage compared to larger networks like the internet. Metrop olitan Area Network A Metropolitan Area Network (MAN) is a network that connects multiple computers and devices across a city or a large area, bigger than a Local Area Network (LAN) but smaller than a Wide Area Network (WAN). It is used by businesses, government offices, or universities to share data and resources over long distances within a city. MANs often use high-speed connections like fiber optics to provide fast communication between locations, such as linking different branches of a company or providing internet access in a city. Wide Area Network A Wide Area Network (WAN) is a type of computer network that connects devices across large distances, such as cities, countries, or even worldwide. Unlike local networks (LANs), which cover small areas like homes or offices, WANs use telephone lines, fiber optics, satellites, or the internet to link computers and networks together. The best example of a WAN is the internet, which connects millions of devices globally. WANs help businesses, organizations, and individuals communicate and share data over long distances. Differences between LAN, MAN and WAN Network Topology Network topology is the way devices are arranged and connected in a network. It shows how computers, servers, and other devices link and communicate with each other. A good network layout helps improve speed and reliability. It decides how data moves, which affects how fast and smooth the network works. A well-planned network reduces delays and traffic, making sure data flows without problems. It also allows new devices to be added easily without causing issues. Understanding and setting up a good network design helps keep communication smooth, supports growth, and ensures data moves efficiently. Star Topology In a star topology, each device is connected directly to a central hub or switch. All communication between devices must go through this central point. It's like a hub-and-spoke model, with the hub being the focal point for data transmission. Bus Topology Imagine a long cable, resembling a bus route, with devices connected along its length. This is the essence of a bus topology. In a bus network, all devices share the same communication channel. Data travels along the cable, and each device checks if the data is intended for it. If so, it accepts the data; otherwise, it ignores it. Think of a school bus with seats for students. In a bus topology, devices like computers and printers are arranged in a line along a single cable, which serves as their communication pathway, similar to the bus route. Ring Topology In a ring topology, each device is connected to exactly two other devices, forming a closed loop or ring. Data circulates around the ring in one direction. When a device receives data, it processes it and passes it along to the next device until it reaches its destination. Advantages Disadvantages Easy to set up Hard to fix problems Works fast Slower speed Can grow bigger easily Limited memory/storage Reliable and stable Security risks Fewer data errors Not very flexible No need for a main computer Hard to connect new devices Simple to solve issues Expensive to set up Saves costs Limits data flow Data moves in one direction Tree topology Tree topology is a type of network structure where devices are connected in a hierarchical way, resembling a tree. It combines elements of both star and bus topologies. At the top, there's a central node called the "root," and from there, branches (or "nodes") spread out, connecting to other devices or smaller groups of devices. Each branch can connect to additional branches, and these branches continue until they reach the leaves (the end devices). In simple terms, think of it like a family tree. The root is the main ancestor, and each level of branches represents different generations or connections, with the leaves being the end devices or computers. Advantages of tree topology: Easy to expand (you can add more branches). Efficient data flow because there are clear paths. Failure in one branch doesn’t affect the whole network. Disadvantages: If the main root fails, the whole network can be affected. It can be more complex to set up and maintain than simpler topologies like star. Mesh topology In mesh topology, all the computers are connected to each other in a network. The connections between devices are made randomly. Computers, switches, hubs, and other devices can all be connected as nodes. If one connection fails, the other devices can still communicate through other paths. Since there is no clear order or pattern between the devices, it can be very expensive. Also, setting up the connections in mesh topology is not easy. Benefits of networking File sharing - you can easily share data between different users, or access it remotely if you keep it on other connected devices. Resource sharing - using network-connected peripheral devices like printers, scanners and copiers, or sharing software between multiple users, saves money. Sharing a single internet connection - it is cost-efficient and can help protect your systems if you properly secure the network. Increasing storage capacity - you can access files and multimedia, such as images and music, which you store remotely on other machines or network-attached storage devices. Disadvantages of networking . Lack of independence. Computer networks involve processes that operate with the help of computers, so people rely more on computer work than on the task at hand. Apart from that, they rely on the main file server, so in the event of a failure, the system becomes unusable and users remain idle. . Lack of independence. Computer networks involve processes that operate with the help of computers, so people rely more on computer work than on the task at hand. Apart from that, they rely on the main file server, so in the event of a failure, the system becomes unusable and users remain idle. . Lack of independence. Computer networks involve processes that operate with the help of computers, so people rely more on computer work than on the task at hand. Apart from that, they rely on the main file server, so in the event of a failure, the system becomes unusable and users remain idle End…….