Operating Systems

• Software that helps to manage the resources of a computer system and provide the interface between the user and the computer’s hardware.

• The OS transfers programs in and out of memory from the hard drive (or virtual memory) when processing is required.

• All programs must be temporarily stored in RAM for the CPU to be able to process them.

• Programs are removed from RAM when closed to free up space for other tasks.

• Appearing that more than one process is being executed at the same time.

• An external device connected to a computer system to input or output data. • Data is transferred between external devices and the processor and this process needs to be managed by the OS.

• A program that provides an interface for the OS to interact and communicate with an external device. • They are hardware dependant and OS specific. • The driver translates the OS’ instructions into a format the specific hardware can understand.

• Because the CPU and the peripheral will process data at different speeds, a buffer is typically used to temporarily store data until it can be processed.

• The OS allows users to create, manage, and delete individual accounts. User accounts can be granted different access rights such as administrator or guest. • The OS will manage security settings such a allowing passwords to be reset and can also be used to monitor login activity.

• The OS creates and maintains a logical management system to organise files and directories (folders).

• File management allows files to be: • named • renamed • opened • copied • moved • saved • searched for • sorted • deleted. • users to set access rights for specific files • to view file properties.

• Allowing a human to interact with the computers system.

• The way in which a user can navigate a computer system.

• Icons are displayed to represent shortcuts to applications and files.

• Multiple windows can be opened at the same time and switched between.

• Interface can be customised e.g changing font sizes and desktop background.

• Folder and file system is displayed and manipulated allowing for copying, searching, sorting and deleting data.

• System settings can be accessed (network, hardware settings).

• Taskbar allows shortcuts to be pinned for quick access.

• Menus can be opened from the Start button to display files and shortcuts.

• Entirely text based • Requires users to interact with the system by typing commands. • Complicated, could accidentally delete data. • Only trained experts can efficiently make use of it.

• Press on a touchscreen • Very intuitive • Suitable for users without training. • Won’t work with dirty/wet fingers • Takes longer to write text than using a keyboard.

• Displays data in a series of linked menus • Cash machines, iPods • User friendly • Easy to use (no commands). • Annoying to find specific data through a large number of menus without a search feature.

• Controlled by speaking commands aloud. • Siri, Google Home, Alexa. • Intuitive • Hands-free • Speed up processes. • Commands may be misheard • Commands may be limited in what can be performed.