[html] disable editing default value of text input

I don't think all the other answerers understood the question correctly. The question requires disabling editing part of the text. One solution I can think of is simulating a textbox with a fixed prefix which is not part of the textarea or input.

An example of this approach is:

<div style="border:1px solid gray; color:#999999; font-family:arial; font-size:10pt; width:200px; white-space:nowrap;">Default Notes<br/>
<textarea style="border:0px solid black;" cols="39" rows="5"></textarea></div>

The other approach, which I end up using is using JS and JQuery to simulate "Disable" feature. Example with pseudo-code (cannot be specific cause of legal issue):

  // disable existing notes by preventing keystroke
  document.getElementById("txtNotes").addEventListener('keydown', function (e) {
    if (cursorLocation < defaultNoteLength ) {
            e.preventDefault();
  });

    // disable existing notes by preventing right click
    document.addEventListener('contextmenu', function (e) {
        if (cursorLocation < defaultNoteLength )
            e.preventDefault();
    });

Thanks, Carsten, for mentioning that this question is old, but I found that the solution might help other people in the future.