What is the Visual Basic "runtime" and do we still need it?

One of the big innovations introduced by Visual Basic was a way to split a program into two parts.

One part is written by the programmer and does everything that makes that program unique, such as adding two specific values. The other part does all of the processing that any program might need such as the programming to add any values. The second part is called the "runtime" in Visual Basic 6 and earlier and is part of the Visual Basic system. The runtime is actually a specific program and each version of Visual Basic has a corresponding version of the runtime. In VB 6, the runtime is called MSVBVM60. (Several other files are also normally needed for a complete VB 6 runtime environment.)

In .NET, the same concept is still used in a very general way, but it's not called a "runtime" anymore (it's part of the .NET Framework) and it does a lot more. See the next question.