The BinaryWriter Object works at lower level of Streams. BinaryWriter is used for write premitive types as binary values in a specific encoding stream. BinaryWriter Object works with Stream Objects that provide access to the underlying bytes. For creating a BinaryWriter Object , you have to first create a FileStream Object and then pass BinaryWriter to the constructor method .

Dim writeStream As FileStream

Dim writeBinay As New BinaryWriter(writeStream)

The main advantages of Binary information is that it is not easily human readable and stores files as Binary format is the best practice of space utilization.

Imports System.IO
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles Button1.Click
        Dim writeStream As FileStream
        Try
writeStream = New FileStream("c:\testBinary.dat", FileMode.Create)
            Dim writeBinay As New BinaryWriter(writeStream)
            writeBinay.Write("This is a test for BinaryWriter !")
            writeBinay.Close()
        Catch ex As Exception
            MsgBox(ex.ToString)
        End Try
    End Sub
End Class