How to close current tab in a browser window?

You will need Javascript to do this. Use window.close():

close();

Note: the current tab is implied. This is equivalent:

window.close();

or you can specify a different window.

So:

function close_window() {
  if (confirm("Close Window?")) {
    close();
  }
}

with HTML:

<a href="javascript:close_window();">close</a>

or:

<a href="#" onclick="close_window();return false;">close</a>

You return false here to prevent the default behavior for the event. Otherwise the browser will attempt to go to that URL (which it obviously isn’t).

Now the options on the window.confirm() dialog box will be OK and Cancel (not Yes and No). If you really want Yes and No you’ll need to create some kind of modal Javascript dialog box.

Note: there is browser-specific differences with the above. If you opened the window with Javascript (via window.open()) then you are allowed to close the window with javascript. Firefox disallows you from closing other windows. I believe IE will ask the user for confirmation. Other browsers may vary.