operating systems

operating systems

1. graphical

   • graphical user interfaces, (GUI) are sometimes referred to as WIMP because they use windows, icons, menus and pointers. operators use a pointing device (such as a mouse, touchpad or trackball) to control a pointer on the screen which then interacts with other on-screen elements. it allows the user to interact with devices through graphical icons and visual indicators such as secondary notations.

2. Menu Driven

   • A menu driven interface is commonly used on cash machines (also known as automated teller machines, ATM'S), ticket machines and information kiosks (for example in a museum). they provide a simple and easy to use interface comprised of a series of menus and sub-menus which the user accesses by pressing buttons, often on a touch-screen device.

3. command line interface

   • command line interfaces are the oldest of the interfaces. it involves the computer responding to commands typed by the operator. tis type of interface has the drawback that it requires the operator to remember a range of different commands and is not ideal for novice users.

4. form based

   • a form based interface uses text-boxes, drop-down menus, text areas, check boxes, radio boxes and buttons to create an electronic form which a user completes in order to enter data into a system. this is commonly used on websites to gather data from a user, or in call centres to allow operators to quickly enter information gathered over the phone.

5. natural language

   • a natural language interface is a spoken interface where the user interacts with the computer by talking to it. sometimes referred to as a "conversational interface", this interface simulates having a conversation with a computer.

6. an operating system has three main functions: manage the computer's resources, such as the central processing unit, memory, disk drives, and printers. (2) establish a user interface, and (3) execute and provide services for applications software.

7. Mac OS X

8. Linux

9. Windows

10. Android

11. IOS

12. functions of the operating system

    • interface-provides a user interface so it is easy to interact with the computer
    • manages the cpu-runs applications and executes and cancels processes
    • multi-tasks- allows multiple applications to run at the same time
    • manages memory-transfers programs into and out of memory, allocates free space between programs, and keeps track of memory usage
    • manages peripherals- opens, closes and writes to peripheral devices such as storage attached to the computer
    • organises- creates a file system to organise files and directories
    • security-provides security through user accounts and passwords
    • utilities- provides tools for managing and organising hardware

13. in a multitasking operating system where multiple programs can be running at the same time, the operating system determines which applications should run in what order and how much time should be allowed for each application before giving another application a turn. it manages the sharing of internal memory among multiple applications. it handles input and output to and from attached hardware devices, such as hard disks, printers and dial-up ports. it send messages to each application or interactive user( or to a system operator) about the status of operation and any errors that may have occurred. it can offload the management of what are called batch jobs(for example, printing) so that the initiating application is freed from this work. on computers that can provide parallel processing , an operating system can manage how to divide the program so that it runs on more than one processor at a time.