Operating System Mind map

Operating System Mind map

1. Device Drivers

   • What they control
     • Peripherals (Low bandwidth I/O systems)
       • Mice
       • Keyboards
       • USB drives
     • Printers
     • Mointers
     • Storage systems
       • Floppy discs
       • Hard disc drives
       • CD Roms
     • Digital Cameras
     • Image Scanners
     • Sound cards
     • Networks cards
     • Modems
   • What they do
     • Provide the software for interfaceing with the hardware
       • Rather than access the device directly, The operating system loads device drivers and calls functions in the drivers to carry out actions on the device
     • Provide input/ouput systems for the hardware
     • Contain a device-specific code for an action on the device

2. Memory Management

   • What does it imply
     • Decide which process are loaded into memory when memory space becomes available
     • Keep track of which part of memory are currently being used and who by
     • Allocate and De-allocate memory space as needed.
   • What types of memory
     • Primary
     • Secondary
       • Virtual
         • memory that appears to exist as main storage although most of it is supported by data held in secondary storage, transfer between the two being made automatically as required.
       • RAM
         • Volatile
         • Recently used programs
       • ROM
         • Non-volatile
         • Stores the instructions for the computer to start up when it is turned on again.
     • Cache
       • Close to CPU
       • Fast access

3. System utilities

   • What does this include?
     • Disk defrag
       • Increases access speed to programs stored on a disk by rearranging the files on it to occupy contiguous storage locations
     • Anti-virus
       • Checks for threats on the computer system and clears them when it is requested the input by the user
     • Firewall
       • keep destructive elements out
       • Prevent unauthorized access to a network
     • Cryptographic
       • utilities that encrypt and decrypt streams and files
   • Why do we need these?
     • Prevents things such as hacking and viruses from damaging networks or systems
     • Encrypt the messages sent and received to prevent the effects of getting the system hijacked
     • Increase the run speed of applications on an disk
     • Increase the user friendliness

4. Kernel

   • What is it?
     • Core of the operating system
       • Allows complete control over everything in the system
     • Opened first on boot-up
     • Handles the rest of the startup as well as input/output request by software
     • usually loaded into a protected area of memory to prevent applications from overwriting it