Computer Components PDF

Chapter 1 This chapter introduces the concept of computers and their role in information processing. It covers the following key points: Electronics Basics: Definitions: voltage, current, low current, strong current, electrical signal, analog signal, digital signal, amplitude, period, frequency,...

Chapter 1 This chapter introduces the concept of computers and their role in information processing. It covers the following key points: Electronics Basics: Definitions: voltage, current, low current, strong current, electrical signal, analog signal, digital signal, amplitude, period, frequency, phase, transmission channel, modulation, bit, flow rate (debit), bandwidth. Electronic Components: active (transistors, diodes, integrated circuits, LEDs) and passive (resistors, capacitors, transformers). Computing Basics: Definition of computer science and computer system. Hardware vs. Software. Brief history of computing machines with 4 generations: 1st generation (1945-1957): Vacuum tubes (ENIAC) 2nd generation (1958-1964): Transistors 3rd generation (1965-1980): Integrated circuits 4th generation (1980-present): Microprocessors (VLSI) Types of Computers: Supercomputers: Very powerful for complex calculations (weather forecasting, scientific research). Embedded computers: Integrated into systems (cars, appliances) for specific tasks. Microcomputers: Most common type, including: Desktop computers: Powerful, separate components for monitor, keyboard, etc. Laptops: Portable, lightweight, battery-powered. Handheld computers (PDAs): Small, for basic tasks like scheduling and note-taking. Tablet PCs: Touchscreen laptops with virtual keyboards or styluses. Body computers: Wearable devices for constant interaction. chapter 2 Hardware vs. Software: Hardware refers to the physical components of a computer you can touch, like the monitor, keyboard, and mouse. Software is the set of instructions that tells the hardware what to do. Main Components: System Unit: This case houses essential components like the CPU (processor), motherboard, memory (RAM), storage drives (hard disk, SSD), graphics card, and power supply. Input Devices: These allow you to interact with the computer, including keyboards, mice, scanners, webcams, microphones, etc. Output Devices: These display or print information processed by the computer, such as monitors, printers, speakers, etc. Detailed Component Breakdown: CPU (Central Processing Unit): The brain of the computer, responsible for executing program instructions. RAM (Random Access Memory): Holds data and programs currently in use (volatile, meaning data is lost when powered off). Storage Devices (Hard Disk Drives, Solid State Drives): Provide permanent storage for data and programs (non-volatile). Motherboard: The main circuit board that connects all other components. Buses: Pathways for data transfer between components. Power Supply: Converts AC power to DC power required by the computer. Ports: Connectors for attaching peripherals like printers, scanners, etc. Graphics Card: Processes video data for display on the monitor. Sound Card: Processes audio data for speakers or headphones. Network Card: Enables network connectivity (wired or wireless). Modem: Allows internet access through a phone line (becoming less common). Monitor: Displays visual information generated by the computer. Keyboard: Primary input device for entering text and commands. Mouse: Point-and-click device for interacting with software applications. Printer: Outputs hard copies of computer data.1 (Types include inkjet and laser) Chapter 3 Here's a breakdown of the key points: Connections: They are crucial for linking electrical components and transmitting data (think of them as computer system's communication pathways). Types of Connections: The chapter details various connectors based on their function, features (color, male/female, etc.), and the components they connect. Power Connectors: These provide power to the computer (mains power socket), motherboard (ATX connectors), and processor (ATX P4 connector). Additional connectors include Molex for internal devices and SATA for Serial ATA devices. Processor Connectors: Processors can connect via slots or sockets depending on the motherboard design. RAM Connectors: These allow you to install RAM memory sticks onto the motherboard. Data Transfer Connectors: DB9 (serial port): Used for connecting mice, cameras, modems, etc. (being replaced by USB). DB25 (parallel port): Used for connecting older printers (obsolete). VGA: Sends analog video signals to monitors. DVI: Sends digital video signals to monitors (being replaced by HDMI). HDMI: Transfers uncompressed multimedia data (audio & video) in high definition. DisplayPort: Another digital interface for transferring multimedia data. PS/2: Used for keyboards and mice (mostly replaced by USB or wireless connections). USB: The most common connector for various peripherals, offering hot-plugging and Plug and Play features. It has gone through several versions with increasing speeds. Storage Connectors: IDE (PATA) is being replaced by the faster SATA for connecting hard drives and optical drives. Expansion Connectors: These allow adding functionality through expansion cards like graphics cards. Examples include PCI, AGP (replaced by PCI Express), which offer varying bandwidths. Audio Connectors: Used for connecting speakers, microphones, etc. They come in different configurations for different outputs. Network Connectors: RJ-11: Connects to landline phones and sometimes modems. RJ-45: Connects the computer to a network. Firewire: High-speed connector for peripherals like digital cameras. The chapter provides visuals for each connector type, making it easier to identify them. chapter:4 An Operating System (OS) is a software that acts as an interface between computer hardware components and the user. It provides services like process management, memory management, file management, device management, and security. Operating systems were first developed in the late 1950s to manage tape storage. Some popular OS include MS-DOS, Windows, and Unix. An OS provides an abstraction layer between the user and the hardware components like CPU, RAM, disks, etc. An OS typically consists of a kernel, shell, file system, user interface, and device drivers. An OS provides various services like process management, memory management, file management, device management, I/O system management, security, and more. Operating systems can be classified into different categories such as batch operating systems, multiprogramming, multi-processing, multi-tasking, time-sharing, distributed, networked, and real-time operating systems. Operating systems can also be categorized based on their architecture, such as 32-bit and 64-bit operating systems. Advantages of using an OS include abstraction, ease of use, resource management, and intermediation between hardware and software. Disadvantages include potential security risks and cost. chapetr 5 Computer Networks: A network allows computers to connect and share resources (data, hardware, software) through physical links (cables) or wirelessly. Network Purposes: Share resources (files, printers, scanners, etc.) Facilitate communication (email, chat) Save time and reduce costs Enable multiplayer gaming Network Classification (by Coverage Area): Personal Area Network (PAN): Covers a small area, connecting nearby devices (phones, laptops). Local Area Network (LAN): Covers a limited geographic area (building, office). Metropolitan Area Network (MAN): Spans a larger area like a city or campus. Wide Area Network (WAN): Covers a large geographical area (country, continent). Network Architectures: Point-to-Point (Peer-to-Peer): Simpler to set up, but less secure and difficult to manage as the number of devices increases. Each device acts as its own administrator, sharing resources with others on the network. Client/Server: More scalable and secure. Relies on a central server that manages resources and fulfills user requests. Clients (workstations) access resources provided by the server. Wired Network Components: Physical Media: These cables carry data between network devices. Common types include: Coaxial cable: Older technology, less common now. Twisted pair cable: Most common type for wired networks, comes in shielded (STP) and unshielded (UTP) variations. Optical fiber: Uses light pulses for data transmission, enabling longer distances and higher bandwidth. Communication Elements: These devices manage data flow within the network. Hub: Concentrates and regenerates network traffic from multiple devices. Switch: Analyzes incoming data and directs it to specific ports. Router: Routes data packets between different networks. Network Topologies: These define how devices are connected in a network. Bus: All devices are connected to a single cable. Simple to set up but vulnerable to failures. Star: Devices connect to a central hub, making the network more reliable but requiring additional hardware. Ring: Devices form a closed loop, with data passing from one to the next. Efficient bandwidth usage but prone to disruptions. Tree: Combines aspects of star and bus topologies, with hierarchical levels. Mesh: Devices connect directly to each other, providing multiple data paths but requiring complex cabling. Chapter 6 Here's a breakdown of the key points: Wireless Networks: These networks allow computers to connect and communicate without physical cables. They use radio waves or infrared signals for data transmission. Benefits of Wireless Networks: o Easier setup: Connects devices within a range (10 meters to kilometers) without modifying existing infrastructure. o Increased mobility: Allows mobile devices to connect to wired networks without cables. o Supports various applications: Enables data, voice, and video transmission for email, web browsing, and telephony. Challenges of Wireless Networks: o Security: Radio waves can be intercepted by unauthorized devices, making networks more vulnerable to hacking. o Interference: Radio waves are susceptible to interference from other devices using the same frequency range. Regulations are needed to manage these frequencies. Classification of Wireless Networks (by Coverage Area):  o Wireless Personal Area Network (WPAN): Covers a few tens of meters, used for connecting peripherals (printers, phones) or PDAs to computers. Bluetooth is a common WPAN technology. o Wireless Local Area Network (WLAN): Covers up to a hundred meters, with technologies like Wi-Fi offering speeds of up to 54 Mbits/s. o Wireless Metropolitan Area Network (WMAN): Connects multiple networks within a city (4-10 kilometers), with WiMax as a popular technology. o Wireless Wide Area Network (WWAN): Covers large areas like cities or countries (hundreds of kilometers) using satellites or infrastructure managed by ISPs. Wireless Network Architectures: o Infrastructure Mode: Uses access points (APs) to facilitate communication between wireless devices. o Ad-hoc Mode: Devices communicate directly with each other without an AP. Wireless Network Reference Model: The TCP/IP model is used for wireless networks, similar to wired networks. Comparison of Wired vs. Wireless Networks: o Wired networks offer higher data rates but lack mobility. o Wireless networks provide mobility but have lower data rates.