Remarks

Named Arguments

Ref: MSDN Named arguments enable you to specify an argument for a particular parameter by associating the argument with the parameter’s name rather than with the parameter’s position in the parameter list.

As said by MSDN, A named argument ,

Optional Arguments

Ref: MSDN The definition of a method, constructor, indexer, or delegate can specify that its parameters are required or that they are optional. Any call must provide arguments for all required parameters, but can omit arguments for optional parameters.

As said by MSDN, a Optional Argument,