Many programming languages have been used nowadays for developing software or tools either in bioinformatics or for other fields.
To explain why VB or C++ is used as a bioinformatic tool, we must first understand that C and C++ were one of the first languages developed. They are the basic ones used in writing programs in the early years, for understanding the concept of programming. One should have basic knowledge of these languages for becoming a good programmer. C and C++ provide many functions for modifying data and they work efficiently if coded for a particular task.
C and C++ are commonly known as middle-level languages which convert the human understandable language into computer language. They are used for writing simple programs and one can develop tools if they gain expertise in these languages. But many people learn these languages only for the base it provides in understanding the concepts of programming and human-machine interface.
C++ is an object oriented programming language which uses class and objects for running the program. They are object based, which means based on objects created by classes. They provide inheritance, polymorphism, data abstraction and data encapsulation. So, it is easy to use and it also works for doing many of the basic tasks of bioinformatics. The main disadvantage of C and C++ is that these two are a bit weak in graphical representation. The graphics of C and C++ are weak and cannot compete with other languages.
VB stands for Visual Basic and it is a great language for developing graphical user interface as the name stands for. It is an event driven programming language where the program is not based on code but it is more based on the event given. Because of this, it is mainly used to develop many tools and software for bioinformatics. One can use VBS (Visual Basic Script) for coding. This is more preferably a offline application and can be run online when it comes with .NET package. Most stand alone bioinformatic software is developed with VB only.