An interrupt vector table (IVT) is a data structure that associates a list of interrupt handlers with a list of interrupt requests in a table of interrupt vectors. Each entry of the interrupt vector table, called an interrupt vector, is the address of an interrupt handler.

In computer science, a vectored interrupt is a processing technique in which the interrupting device directs the processor to the appropriate interrupt service routine. This is in contrast to a polled interrupt system, in which a single interrupt service routine must determine the source of the interrupt by checking all potential interrupt sources, a slow and relatively laborious process.

In computer systems programming, an interrupt handler, also known as an interrupt service routine or ISR, is a special block of code associated with a specific interrupt condition. Interrupt handlers are initiated by hardware interrupts, software interrupt instructions, or software exceptions, and are used for implementing device drivers or transitions between protected modes of operation, such as system calls.

<software> A routine which is executed when an interrupt occurs. Interrupt handlers typically deal with low-level events in the hardware of a computer system such as a character arriving at a serial port or a tick of a real-time clock. Special care is required when writing an interrupt handler to ensure that either the interrupt which triggered the handler's execution is masked out (inhibitted) until the handler exits, or the handler is re-entrant so that multiple concurrent invocations will not interfere with each other. If interrupts are masked then the handler must execute as quickly as possible so that important events are not missed. This is often arranged by splitting the processing associated with the event into "upper" and "lower" halves. The lower part is the interrupt handler which masks out further interrupts as required, checks that the appropriate event has occurred (this may be necessary if several events share the same interrupt), services the interrupt, e.g. by reading a character from a UART and writing it to a queue, and re-enabling interrupts. The upper half executes as part of a user process. It waits until the interrupt handler has run. Normally the {operating system} is responsible for reactivating a process which is waiting for some low-level event. It detects this by a shared flag or by inspecting a shared queue or by some other synchronisation mechanism. It is important that the upper and lower halves do not interfere if an interrupt occurs during the execution of upper half code. This is usually ensured by disabling interrupts during critical sections of code such as removing a character from a queue. (2002-07-24)

A raster interrupt (also called a horizontal blank interrupt) is an interrupt signal in a legacy computer system which is used for display timing. It is usually, though not always, generated by a system's graphics chip as the scan lines of a frame are being readied to send to the monitor for display.

In epidemiology, a disease vector is any living agent that carries and transmits an infectious pathogen to another living organism; agents regarded as vectors are organisms, such as parasites or microbes. The first major discovery of a disease vector came from Ronald Ross in 1897, who discovered the malaria pathogen when he dissected a mosquito.

<graphics> (Sometimes called "object-oriented" graphics, though it's nothing to do with object-oriented programming). The representation of separate shapes such as lines, polygons and text, and groups of such objects, as opposed to bitmaps. The advantage of vector graphics ("drawing") programs over bitmap ("paint") editors is that multiple overlapping elements can be manipulated independently without using differenet layers for each one. It is also easier to render an object at different sizes and to transform it in other ways without worrying about image resolution and pixels. (2001-02-06)

The Interrupt Descriptor Table (IDT) is a data structure used by the x86 architecture to implement an interrupt vector table. The IDT is used by the processor to determine the correct response to interrupts and exceptions.

Vector graphics is a form of computer graphics in which visual images are created directly from geometric shapes defined on a Cartesian plane, such as points, lines, Curves and polygons. The associated mechanisms may include vector display and printing hardware, vector data models and file formats, as well as the software based on these data models (especially graphic design software, computer-aided design, and geographic information systems).