C# is a compiled language, while the old asp was typically written in VB Script which is an interpreted language, so you didn't have to worry about all that compiling issues :)
Having a 'using System.Globalization' doesn't say much, that namespace can exist in any number of assemblies, but if its ie. the CultureInfo class you're using, its a class that exists in mscorlib, which is an so important assembly that you actually have to explicitly say you don't want to reference it, otherwise its automatically used during compilation.
/nostdlib prevents the import of mscorlib.dll, which defines the entire System namespace. If you do not specify /nostdlib, mscorlib.dll will be imported into your program...
https://msdn.microsoft.com/en-us/library/fa13yay7.aspx
Having a 'using System.Globalization' doesn't say much, that namespace can exist in any number of assemblies, but if its ie. the CultureInfo class you're using, its a class that exists in mscorlib, which is an so important assembly that you actually have to explicitly say you don't want to reference it, otherwise its automatically used during compilation.
/nostdlib prevents the import of mscorlib.dll, which defines the entire System namespace. If you do not specify /nostdlib, mscorlib.dll will be imported into your program...
https://msdn.microsoft.com/en-us/library/fa13yay7.aspx