Slowly playing and trying things to learn ASP.NET when time permits...

I have a simple page with a submit button so I can see how it goes to the next page (child's play, right?)

I have the following button:

< asp:button id="btnNext" runat="server" Text="Next" Onclick="btnNext_Click" >< /asp:button >

"default.aspx.cs" has the following excerpt:

private void btnNext_Click(object sender, System.EventArgs e)
{
   Response.Redirect("page2.aspx");
}

I get the following compiler error:

myproj.WebForm1.btnNext_Click(object, System.EventArgs)' is inaccessible due to its protection level

If I change "private void" to "public void" it works. Why is private not accessible?