For what is the method openFileOutput() used for Android Studio? : I have this snippet of code. Can someone please help what '0' attribute in openFileOutput stands for in the following code?
`public void Save(String fileName) {
    try {
        OutputStreamWriter out =
            new OutputStreamWriter(openFileOutput(fileName, 0));
        out.write(EditText1.);
        out.close();
        Toast.makeText(this, "Note Saved!", Toast.LENGTH_SHORT).show();
    } catch (Throwable t) {
        Toast.makeText(this, "Exception: " + t.toString(), Toast.LENGTH_LONG).show();
    }
}` 