Operating System Fundamentals

New or Exit. This task is usually the responsibility of the operating system. State machine – a diagram used to illustrate the states of a machine (computer, and the actions that would cause the machine to change its state.
Subdirectory – a directory that has been created inside of another directory (see Subfolder).
Subfolder – a folder that has been created inside of another folder (see Subdirectory). Swap file – a portion of a storage device (typically a hard disk) that has been allocated for use as virtual memory (see Page file). Swapping – exchanging pages between RAM and virtual memory when pages residing in virtual memory are needed by a process being executed by the CPU.
Symbian – A specialized operating system used by mobile devices. Synchronization – a system where multiple processes (or threads) must coordinate in someway to share resources and to perform required actions in a predetermined order. Synchronization variable – variables that are used to help coordinate communication, the sharing of resources, and the scheduling of actions between processes (or threads.

Operating System Fundamentals
100 System bus – the main data path (usually 32, 64 orbits wide, depending upon the type of motherboard) that connects the CPU to RAM, the graphics controller, and all of the IO busses. System call – Processes that have been converted into system actions to be executed by the CPU. System clock – component on a motherboard that regulates the timing of processes carried out by a computer system. System software – An operating system. Take – an operation where a thread requests a signal (semaphore, and then either takes control if the signal is available, or goes into a blocked state until the signal is available (see
Wait). Thrashing – a condition that exists when the memory manager is swapping pages between RAM and virtual memory too frequently. Thrashing can result in increased processing time and undue wear and tear on a hard disk. Thread – a single sequence of instructions to be executed. Often a subset of instructions (or a
mini-program) that is part of a larger program. Time slice – the amount of time assigned by the Process Scheduler fora process to execute have the attention of the CPU) (see Quantum). Traces – Metal lines on circuit boards used to transmit electronic data in binary form. Track – a concentric circle on the surface of a magnetic storage disk. UNIX – A command line interface operating system designed in the s for large scale computer and network systems.
Unbuffered – data transfer that does not use a buffer to temporarily hold the data before it is transmitted to a device.
Unmanaged exception – an error that cannot be handled by the program currently being executed. Upper Half – part of a device driver that handles taking requests from the operating system and placing them into the shared requests folder so that they can be programmed to be carried out by the device. USB – Universal Serial Bus. An IO bus designed for newer, high-speed Input and Output devices. USB controller – a specialized device controller that handles controlling all devices connected to a computer by USB. User mode – The operating system level accessed directly by the user to run applications.

Operating System Fundamentals
101 Variable – a value that can be changed, and that is used to help determine the actions to betaken by a set of program instructions. Virtual computer – A simulated computer operating system run from inside of another operating system using a virtualization application. Virtual memory – a system that uses part of a storage device (typically a hard disk) to act as if it is extra RAM, thereby increasing the total amount of memory available for processing. Virtual memory space – a memory addressing system maintained by the memory manager to allocate space to pages in both physical and virtual memory. Virtualization – Simulating an operating system using a virtualization application to translate one operating systems functions into instructions understand by the actual operating system. Volatile memory – RAM memory that loses its contents when its power supply is interrupted. Voltage good line – a wire used by the computer to test electrical voltage when the system is first turned on.
VxWorks – A specialized operating system for aircraft systems. Wait – an operation where a thread requests a signal (semaphore, and then either takes control if the signal is available, or goes into a blocked state until the signal is available (see Take). Windows Explorer – a file management tool provided by Windows operating systems. Windows Mobile – A specialized operating system for mobile devices. Windows Ready Boost – a feature of newer Windows operating systems (Windows Vista and Windows 7) that allows removable storage devices (such as USB flash drives) to be used to expand virtual memory. Worst fit – a memory allocation strategy that finds the largest available free space in RAM to store date. The idea is to minimize wasted space in RAM by leaving behind the largest possible chunk of free space, thereby increasing the possibility that the memory fragment will be large enough to be useful to another process.

Operating System Fundamentals
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References
Andrews, Jean (2007). A+ Guide to Managing & Maintaining Your PC Comprehensive, 6 ed. Edition Canada Thompson Course Technology Palmer, Michael and Walters, Michael. (2007). Guide to operating systems, enhanced edition. Boston, MA, USA Thomson Course Technology.
Stallings, William (2009). Operating systems Internals and design principles. 6 ed. Upper Saddle River, NJ, USA Pearson Education International. View publication stats