Código HTML:
<html>
<head>
<script type="text/javascript">
function Atras()
{
window.history.back();
}
function Palante()
{
window.history.go(1);
}
</script>
</head>
<body>
<input type="button" name="Atzera" value="Atzera" onCLick="Atras()" />
<input type="button" name="Aurrera" value="Aurrera" onCLick="Palante()" />
</body>
</html>