<input type="button" value="按钮"
onclick="javascrtpt:window.location.href='http://www.baidu.com/'" /> 

<button onclick="window.location.href = 'https://www.baidu.com/'">百度</button> 

<a href="http://www.baidu.com/">
    <button>百度</button>
</a> 

<a href="http://www.baidu.com/"><input type="button" value='百度'></a> 

<script>
function jump(){
 window.location.href="http://www.baidu.com/";
}
</script>
<input type="button" value="百度" onclick=javascrtpt:jump() />
// 或者<input type="button" value="百度" onclick="jump()" />
// 或者<button onclick="jump()">百度</button>