i'm playing around with javascript and tried the following:
//a.js
HTML Code:
function  oculta() {
    var paragrafo = document.getElementById("a");
    paragrafo.style.displays = 'hide';
}
window.onload = oculta;
//test.htm
HTML Code:
<html>
<head>
<title></title>
<style type = "text/css"></style>
<script type = "text/javascript" src = "a.js"></script>
</head>
<body>
<p id = "a" >bla bla</p>
</body>
</html>
but nothing happens, either i use 'none', or '' or even 'hide'
what am i doing wrong?

TiA