A quad core processor is a single unit made up of four independent cores that process fixed-length or variable-length data. Each of the four cores works independently to read and execute computer program instructions, which might include data and memory functions. The multi-processor allocates different processes to individual cores using a method known as multitasking. This method can help a supported operating system (OS) run more efficiently, especially when allocating processing power to multiple resource intensive applications at the same time.
While a quad core processor supports multitasking, it is the OS that determines how well a computer system will handle running multiple applications at once. Multitasking depends upon frequent context switching of tasks to produce the illusion of parallel running applications. Since it has more cores, a quad core processor is in theory able to handle tasks more quickly than single or dual core processors. In practice, however, there are multiple reasons that quad core processors may not actually be any faster.
Despite the perception that more cores should equal faster processing, the quad core processor's improvement in performance over its predecessors depends on application use and implementation. Quad core processors in computer systems are generally marketed toward users who run resource intensive applications such as video games, video editing software, and graphic editors. Many video games are written so that they make optimal use of multi-processors.
Software that supports multi-threading, like many video and graphic editors, does not handle tasks in a linear fashion. Instead, tasks are executed in parallel across multiple processors or cores. Mainly due to better multi-threading capabilities, many benchmark tests have shown that quad core processors allow for faster video encoding, rendering and editing speeds compared to single and dual core processors.
In addition to dual and quad core processors, processors with even greater numbers of cores are being developed and implemented. As with earlier multi-core processors, adding even more cores holds the promise of still larger increases in processing speed. The ability to realize these speed gains, however, seems to depend on software design that can take advantage of the newer technology to process data in parallel across the number of available cores.