Untitled

<html>
<head>
<meta charset="utf-8">
</head>
<body>
</body>
<script src="script.js"></script>
</html>

<script type="text/javascript">

var username = prompt ( "Пожалуйста, введите ваш логин(Имя):", "" );
var password = prompt ( "Пожалуйста, введите ваш пароль:", "" );

if ( username && password)
{
	set_cookie( "username", username );
	set_cookie( "password", password );
	var username = get_cookie ( "username" );
	var password = get_cookie ( "password" );
	alert('Ваши данные\n' + username + '\n' + password);
}

function set_cookie ( name, value )
{
	var cookie_string = name + "=" + escape ( value );
	document.cookie = cookie_string;
}

function get_cookie ( cookie_name )
{
	var results = document.cookie.match ( '(^|;) ?' + cookie_name + '=([^;]*)(;|$)' );

	if ( results )
		return ( unescape ( results[2] ) );
	else
		return null;
}
</script>