VESA BIOS Extensions (VBE) comprise a VESA standard, currently at version 3, that defines the interface that can be used by software to access compliant video boards at high resolutions and bit depths. This is opposed to the "traditional" int 10h BIOS calls, which are limited to resolutions of 640×480 pixels with 16 color (4-bit) depth or less. VBE is made available through the video adapter's BIOS, which installs interrupt vectors pointing at itself during system startup.

Unfortunately, the older versions of VBE (those bundled with older video cards) supported only a real mode interface, which could not be used without a significant performance penalty from within protected mode operating systems, such as Windows 95 or Linux. This meant that the VBE standard was almost never used for writing video-drivers, and each video board vendor had to invent a proprietary protocol for communicating with their own boards. Despite this, many existing drivers for these video cards still thunk out to the real mode interrupt to initialize screen modes and gain direct access to a card's linear frame buffer, tasks which would otherwise require many hundreds of port writes which change from card to card.

Most newer cards support the more capable VBE 3.0 standard. This standard provides the primary functionality of the VESA BIOS Extensions. It allows applications to determine the capabilities of the graphics card and provides the ability to set the display modes that are found.

VBE 2.0 adds some new features above the prior VBE 1.2 standard including linear framebuffer access and protected mode banking. Some of the VBE Core 2.0 features include: A superset of the VBE 2.0 standard. This standard adds refresh rate control, support for stereo glasses, improved multi-buffering support and other functions to the VBE 2.0 standard.

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