For certain classes of operations, a modern GPU can crunch numbers significantly more quickly than the general-purpose processor at the heart of a personal computer.

Life would be a lot easier for applications developers if there was a standardised way of using those capabilities.

And that's what OpenCL delivers: an API that enables the use of all computational resources in a system, including GPUs, CPUs, DSPs, Cells and other processors, with portability across hardware.

It's based on the C language (more precisely, it's an extended subset of ISO C99), so many developers will be comfortable with it.

Furthermore, OpenCL is designed to work alongside OpenGL (which is another Khronos standard), efficiently sharing hardware resources and data. For example, OpenCL might be used to generate image data before it is rendered by OpenGL.

It normally takes years for industry bodies to establish standards, but Khronos Group created the public specification for OpenCL in less than six months.

Participants in Khronos Group's OpenCL effort include 3DLABS, Activision Blizzard, AMD, Apple, ARM, Barco, Broadcom, Codeplay, Electronic Arts, Ericsson, Freescale, IBM, Intel, Motorola, Nokia, NVIDIA, QNX, RapidMind, Samsung, and Texas Instruments.

The involvement of Intel, AMD (which owns ATI) and NVIDIA means OpenCL is likely to gain wide support in the industry.

What do key participants have to say, and what's ahead for OpenCL? Please read on.

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Intel's vice president and general manager of its visual computing software division Elliot Garbus said "Over the years Intel has worked closely with the industry to innovate through open standards and is a long standing member of the Khronos board of promoters.

"With the introduction of OpenCL, we see new opportunities for developers to innovate through a task- and data-parallel programming environment that can benefit from the performance and flexibility of current and future Intel products."

Speaking for AMD,  Rick Bergman, senior vice president and general manager of the graphics products group said "AMD believes that broad adoption of industry standards by hardware and software vendors is essential to successfully harnessing the power of stream computing in a wide array of mainstream applications.

"AMD has consistently supported an open, industry standards approach to stream computing, and is an aggressive proponent of the OpenCL standard."

As for NVIDIA, Tony Tamasi, senior vice president of technical marketing, said "OpenCL adds fuel to the most exciting parallel computational revolution of our generation – GPU computing.

"It also provides another powerful way to harness the enormous processing capabilities of our CUDA-based GPUs on multiple platforms."

And we mustn't miss out Apple: "We are excited about the industry-wide support for OpenCL," said Bertrand Serlet, Apple's senior vice president of software engineering.

"Apple developed OpenCL so that any application in Snow Leopard, the next major version of Mac OS X, can harness an amazing amount of computing power previously available only to graphics applications."

Another factor that should speed the adoption of OpenCL is that there is no charge to developers who wish to use it, although anyone that implements OpenCL itself must pay for conformance testing before they can use the trademark.

Future plans for OpenCL include an embedded profile that would allow compute-intensive applications to run on handheld devices with extreme power efficiency.