refer https://en.wikipedia.org/wiki/Comparison_of_C_Sharp_and_Visual_Basic_.NET

Visual Basic and C# are programming languages designed for creating a variety of applications that run on the .NET Framework. Visual Basic is a third-generation event-driven programming language and integrated development environment (IDE) from Microsoft for its COM programming model first released in 1991 and declared legacy in 2008. Microsoft intended Visual Basic to be relatively easy to learn and use and c# is derived from the c language as a alternative to java by Microsoft first version of c# was released in year 2000

Simple, its the way we write syntax definition is different, apart from that in concept wise both are same. its just two different language to write the code.

check this http://www.codeproject.com/Articles/9978/Complete-Comparison-for-VB-NET-and-C