ITC 191 Final 2
Terms in this set (70)
A program or set of programs that managers the operations of the computer. Acts as a bridge between the user and the hardware, as a user cannot communicate directly with the hardware.
Controlling and coordinating the use of memory in a computer.
Dividing memory into fixed size pages each one being 4 kilobytes.
A form of memory management in which data or programs are split into segments of varying length depending program structure.
When RAM is full, the hard disk is used as a temporary extension of main memory .
A shared boundary across which two separate components of a computer system exchange information. The exchange can be between software, computer hardware, peripheral devices, humans and combinations of these.
A signal from software, hardware or internal clock to the CPU.
A small program held in ROM. When a computer is switched on this program sends instructions to load the operating system, by copying it from storage to RAM.
Interrupt service routine
A particular routine called to deal with an interrupt.
A set of instructions to be followed by the CPU.
Processes are dispatched on a first in first out (FIFO)
basis, with each process in turn being given a limited amount of CPU time, called a time slice.
First come first served
Jobs are processed in the order in which they arrive, with no system of priorities.
Multi level feedback queues
This algorithm is designed to give preference to short jobs, give preference to input/output bound processes and separate processes into categories based on their need for the processor.
Shortest job first
The process with the smallest estimated running time is run next. Refers to the running of a fresh, new program that has not yet been run.
Shortest remaining time
The process with the smallest estimated time to completion is run next. This process has already been started.
Computer storage that keeps the data or its contents regardless if the power is turned off or if the storage device is moved to another computer.
When the operating system allocates a particular area of memory to store a program that is currently running.
How the processor allocates processor time to one task when the computer is running several tasks at the same time.
Software that is used to complete a specific task. e.g. make a spreadsheet or view a web page
The process of having a computer perform multiple tasks simultaneously. Tasks such as listening to a CD or browsing the Internet can be performed in the background while using other programs in the foreground such as an e-mail client.
power fail interrupt
Interrupt with the highest level of priority.
A "timesharing clock" interrupts the CPU at regular intervals and allows the operating system to divide its time between tasks.
input output device
A low priority interrupt where a mouse or keyboard sends a signal to the CPU.
A special data structure that removes items in the reverse order from which they were added.
Total amount of time it takes to respond to a request form the operating system.
First in first out
A method of processing data where the data first received is the first to be sent out after processed.
The set amount of processing time each user gets.
An area of memory that compensates for the difference in speed between the CPU and an output device like a printer.
distributed operating system
A form of parallel processing system which spreads the load over multiple computer servers.
When a single job is split into several tasks and each of these is run on a separate processor, coordinated by the operating system.
multi user multi tasking system
When a single powerful mainframe or supercomputer is connected to hundreds of terminals all using the same mainframe CPU. Each user gets a slice of the processing time according to a scheduling algorithm.
mobile operating systems
OS designed to run on a smart phone or tablet computer using a touch screen interface.
real time operating system
An operating system intended to serve real-time applications which process data as it comes in, typically without buffering delays.
embedded operating system
These operating systems are designed to be compact, and efficient at using very limited in resources such as RAM and ROM.
Operating system designed to do specific tasks.
Creators often write them in assembly.
Does not load and execute applications.
Only able to run a single application.
An operating system for embedded computer systems.
Sometimes called real-time operating systems.
basic input output system
What does BIOS stand for?
erasable programmable read only memory
What does EPROM stand for?
A program that operates or controls a particular type of device that is attached to a computer.
When an operating system is run within another to emulate different hardware.
A program (as an operating system or compiler or utility program) that controls some aspect of the operation of a computer.
A program that performs a specific task related to the management of computer functions, resources, or files, as password protection, memory management, virus protection, and file compression.
open source software
Software with source code that anyone can inspect or modify.
closed source software
Software with source code that is not available to the public because it is copyrighted.
A computer program or application that changes one language or data format into another.
A collection of standard programs and subroutines that are stored and available for immediate use.
off the shelf software
Software that may contain a lot of unwanted features, be ready to install immediately, well tested and error free. e.g. Microsoft Word
custom written software
Another name for bespoke software.
Sometimes referred to as closed source software.
Software legally remains the property of the organisation who created it.
The organisation that owns the rights to the product usually does not release the source code.
Only those who have purchased a special licence key can use it.
A utility in Microsoft Windows designed to increase access speed by rearranging files stored on a disk to occupy contiguous storage locations.
A utility that makes an exact copy of data to protect it and facilitate recovery if data is lost, corrupted or infected.
Utility program that ensures that software is up to date by installing the more recent version automatically.
A utility, sometimes known as anti-malware software, is computer software used to prevent, detect and remove malicious software.
A utility that packages files to use less disk space.
This includes software programs that will archive your files and extract archived files such as ZIP and RAR files.
Many products in this category let you manage files and protect them with encryption.
Notable titles include WinZip, WinRAR, and 7-Zip.
general purpose software
Software that can be used for many different purposes. For example a graphics package may be used to produce adverts, animations or edit photographs. e.g. Serif Draw plus x4.
special purpose software
Software that performs a single specific task. e.g. payroll and accounts packages, hotel booking systems or browser software.
Software created for a company or individual for a specific purpose, but not available to the public.
Software is free, but the user cannot access the source code.
A program for converting instructions written in low-level symbolic code (mnemonics) into machine code.
A program that takes basic computer instructions and converts them into a pattern of bits that the computer's processor can use to perform its basic operations.
A program that processes statements written in a higher level programming language like C or Pascal and turns them into machine language or "code" that a computer's processor uses.
Typically, a programmer writes language statements in a language such as Pascal or C one line at a time using an editor.
A program that can analyse and execute a program, written in a high level language, line by line.
The proves of translating high-level instructions directly into machine language.
Another name for object code that is processed by a virtual machine, rather than by the "real" computer machine.
The result of compiling source code written in a language that supports this approach. e.g. Java
The best-known language today that uses the byte code and virtual machine approach is Java.
Programming code that, once compiled, is run through a virtual machine instead of the computer's processor
low level language
A programming language with commands or functions that map closely to processor instructions.
Generally this refers to either machine code or assembly language
The elemental language of computers, comprising a long sequence of binary digital zeros and ones (bits).
A group of commands for a CPU in machine language.
A sequence of assembler instructions, written in assembly language.
The output of the assembler program is called the object code or object program.
The sequence of 0's and 1's that make up the object program is sometimes called machine code.
A program that executes a byte code program.
An example is the Java Virtual Machine.
Software that can run on any hardware or software platform are said to be this.
In general, programs written in Java language can be executed on practically every platform.
java virtual machine
Once installed on any platform (like windows or OS) it can run java code without any alteration.
It acts like a virtual platform on which the code is executed.
It way it works remains constant throughout all platforms, so Java programs can run on any platform.
What a computer compiler produces.
A sequence instructions in machine code.