1. XLL SDK;
2. Shared Add-in (COM add-in)
3. Excel Add-in (C# VSTO)
4. Excel Workbook (C#)
5. Excel Template
6. VBA

and advatages and disadvatages?

I personal think C# is depend on .NET Framework 3.5, so it's not good for me
,but I also want to know it's advatages compare with other type Excel
application.