A VB file is a project item file written in the Visual Basic language, an object-oriented programming language created by Microsoft for use with the .NET Framework. It contains Visual Basic instructions in ASCII text format.
A project item can refer to a variety of Visual Basic project components. Each available project item differs based on whether you are working in a local or web project. Examples of project items include a Windows form, Login form, splash screen, dialog, class, interface, code file, custom control, web custom control, or installer class. The "vb" extension is used for all of these items.
Visual Basic is a programming language implemented on the .NET framework. Visual Basic .NET (VB.NET) was released in 2002 to replace the original Visual Basic language. The VB.NET language is used to create applications based on .NET, such as web applications and XML web services. ".NET" was eventually dropped by Microsoft in 2005 and the VB file is now used by Microsoft Visual Studio.
NOTE: VB files can also be used to contain viruses or other malware. Therefore, do not open VB files if they are an unknown e-mail attachments.