To study "ASP.NET 2008 C#" is useful to know VC#2008/VC#.NET2008 or does not matter ? or is required to have knowledge ? same with VB ?

exist any difference between VB.NET 2008 (and/or VC#.NET 2008) from ASP.NET 2008 ? can you tell me 2-3 main points ? or is exactly identical ?