unit 2 fundamentals of comp

• Multifunctional device

  A device that is capable of performing multiple functions
• Motherboard

  Acts as central interface where all components are connected to it
• Power supply

  Provides power and regulates the motherboard
• Hard disk drive

  • Stores software and data permanently
  • Data is stored on an invisible magnetic tracks on the disc using a read/write head which moves on the track then copy the data from the track to RAM (read) or records data from RAM to the track (write).
• Server

  Provides services for other computers on the network
• File server

  A device which controls access to seperately stored files, as part of a multi-user system
• Print server

  A software application/network/computer device that manages print queues
• Security server

  Protects users from malware, unauthorised access, data breaches and misusages
• Backup server

  Allows for mutiple copies of data + recover them immediately when primary server fails
• Web server

  A computer that runs websites
• Communication server

  Allows mutiple computers to access communication lines that are connected to the device (various networking)
• Application server

  Hosts applications/software that delivers a business application through a communication protocol
• Domain name system server (DNS)


  Stores IP addresses and domain names
• Dynamic host configuration protocol server (DHCP)


  Assigns an IP address to any device, node, or network so it can communicate using IP
• Access control server


  Controls access to different parts of the device
• Maintenance server

  Involves keeping a server updated and running so that a computer network can operate smoothly
• Servers must....

  • Stay on for 24hrs
  • Must be reliable
  • Have large RAMS
  • Have faster processors
  • Be accessed by multiple users
  • Have high speed network interfaces
• Factors that affect choice of internal components

  • Personal
  • Education
  • Social
  • Retail
  • Organisational
  • Creative work
• Input device


  Data is sent to the computer through a peripheral device to be processed and is controlled by the user
• Examples of input devices

  • Mouse
  • Keyboard
  • Joystick
  • Microphone
  • Scanner
• Output device


  Processed data is shown on user's device and is controlled by the computer itself
• Examples of output devices

  • Monitor
  • Printer
  • Speaker
  • Projector
  • Headphones
• Embedded system

  A small computer within a larger computer system that requires user interface
• Single board computers

  Small, inexpensive complete computers designed for development projects
• Modular smartphones

  Features can be changed by user to change functionality
• Main memory

  Stores data that can be accessed by the processor in the RAM
• Cache memory

  Holds frequently accessed data and is closer to the CPU making it faster than RAM
• Random access memory (RAM)


  Used for the storage of programs and data currently in use

  
  

  • Volatile
• Read only memory (ROM)


  Permanent area of storage for programs and data that have been installed during the process of computer manufacture

  • Non volatile
• Application software

  Designed to perform 1 task

  • e.g. word processor, internet browser, email
• System software

  Provides a stable environment for the application software
• 5 types of system programs

  1. Utility programs
  2. Library programs
  3. Compilers
  4. Assemblers + interpreters
  5. Operating system
• Utility programs ("housekeeping" programs)

  • Designed to enhance the use of the computer and its programs
  • Supplied with the OS or can be purchased seperately
• Library programs

  
  

  • Written to carry out common tasks
  • Pre-written code that can be used by other programs, which are crucial for certain applications to run
• Operating system software

  Acts as an interface between the user and the computer as well as managing the overall operation of the computer

  USER

  |

  APPLICATION

  |

  OPERATING SYSTEM

  |

  HARDWARE
• Functions of the operating software system

  • Controls the start-up configuration
  • Recognises when a mouse/keyboard has been pressed
  • Controls print queues
  • Manages users on a network
  • Makes sure computer shuts down properly
• OS memory management

  Stores details of unallocated locations in a section of memory known as the "heap"
• Resource management

  Refers to all of the other resources at the disposal of the operating system
• Kernel (Bridge between applications + data processing)


  A computer program at the core of computer's operating system, that manages communication between the software, CPU and disk memory

  It controls:

  • Disk management
  • Memory management
  • Task management
• Open source software


  • Possible to edit and change os software
  • Have access to source code
  • Cheaper to implement
  • Can be closely customised to match organisations' requirements
  • Relies on peer review