what is meant by pre-define error that may occur in vb application

Question

what is meant by per-defined error that may occur in VB application.

Vulpes · Answer

The pre-defined exception classes are those which are defined in the .NET Framework itself. They include common exceptions such as : FormatException InvalidCastException NullReferenceException and OutOfMemoryException. However it's possible to define your own 'custom' exceptions by inheriting (directly or indirectly) from the System.Exception class which is the base class for all exceptions in .NET.