Short for Visual Basic Extension, a reusable software component designed for use in many different applications. While VBXs can be used in other environments, they were initially created for developing Windows applications with Visual Basic. An application developer can use a number of selected VBXs to quickly develop an application. While similar to objects, VBXs do not have two of the properties (inheritance and polymorphism) required by true object-oriented systems.
Many different companies offer specialized VBXs for tasks such as controlling instruments or image handling. However, VBXs are being superseded by ActiveX controls, which are more flexible.