placeholder，显示描述信息

<form action="">
    <input type="search" name="keyword" placeholder="长乐未央">
</form>

autocomplete，自动完成

<form action="" autocomplete="on">
    昵称：<input type="text" name="nickname"><br><br>
    E-mail：<input type="email" name="email" autocomplete="off"><br><br>
    <input type="submit" value="提交">
</form>

![2.png](https://assets.clwy.cn/upl...