Passing Arguments To Procedures

Formula:

Sub Main()

	Dim MyValue As Integer

	MyValue = 10

	Call Process(MyValue)

	MsgBox MyValue

End Sub



Sub Process(ByVal YourValue)

	YourValue = YourValue*10

End Sub

1) Is MyValue = YourValue here (10)? (Because it's argument of the same method.)

2) If so Why they are written the same as "MyValue"?

3) Sometimes there is not a argument next to ByVal, ByRef. Why?