DirectX is a family of "application program interfaces" (APIs) that are designed by Microsoft to make graphics functionality of Microsoft compatible software -especially videogames - function smoothly and at their highest level. There have been DirectX versions 3,5,6,7,8,9 and now, concurrent with the introduction of the new Microsoft Vista operating system, DirectX 10.

Direct3D is a special interface designed by Microsoft that allows developers to abstract 3D graphics programming from the underlying hardware. First introduced with Windows 95 11 years ago, Direct3D and its parent API, DirectX, have been a mainstay in the 3D games development industry.

Each version of DirectX has caused the development of more powerful and sophisticated video cards - the big manufacturers are ATI and nVidia - as the graphics, special effects and images on screen become less cartoon-like and more realistic. The essential goal of DirectX has always been to develop an onscreen 3-D environment, and every version of DirectX has improved upon that goal. With the introduction of each version of DirectX, the video card companies have been forced to produce new cards able to take advantage of the latest DirectX version's new features.

As of DirectX 10, to be introduced in Windows Vista, all 3D vendors (game makers) will support the same features, guaranteeing compatibility across the board. Although this may sound great, allowing for a more standardized games development environment, it makes it harder for graphics card makers to create more unique products and differentiate themselves in the marketplace.

Vista and DirectX 10 aren't all doom and gloom for the games industry, according to a Microsoft spokesman. They will in fact do much for both the performance and versatility of graphics hardware. For instance, graphics processors, known as GPUs, will have scheduling and sharing capabilities under Vista, much like CPUs have now. Users will be able to run multiple 3D applications that will be able to share memory, GPU cycles and other resources, something that is currently impossible under previous Windows versions.

While this is computer happy talk for compatibility, it may also portend a necessary function demanded by the sheer size of the Vista program and the power needed to drive video MB and RAM hungry games along with the operating system itself. Nevertheless, Vista was certainly designed with multimedia in mind. It will be the first Microsoft operating system designed to run on both 32 bit and the new generation of 64 bit chips - a quantum step forward in computer speed and sophistication.

According to video card maker ATI, the big step forward provided by DirectX 10 is a fundamentally different method of integrating what are called "vertex" and "pixel" shader functions into a "geometry" shading process. What this means is that the process of producing high quality graphics does not require substantial use of the CPU, or the computer's processing unit, but rather relies on the graphics processing unit - the video card. That means a lot less interchange of information between the computer's central functioning units and the video card - and thus, a chance for game developers to produce a more sophisticated and detailed 3D image that is less susceptible to distortion.

Gamers, start your engines.