The HTML <u> tag shows a short part of written text that should be displayed to suggest it has extra information. By default, this is shown as a plain line under the text. But you can change it using coding style CSS.
The <u> tag shows some words that are not clear and made to look different from regular text, like wrongly spelled words or proper names in Chinese writing. The stuff inside is usually shown with a line under it. You can change this using CSS (see example below).
HTML Example
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset ="UTF-8">
<!--This is our webpage it's our very first webpage-->
<title>Levoric | HTML Fundamentle Tutorial</title>
<link rel="stylesheet" href="style.css">
</head>
<body>
<!--Write your content here levoriclearn top degree online and program-->
<p>Welcome to <u> Levoric</u>Learn <u> Educational</u> Website</p>
<!--Write your content here levoriclearn top degree online and program-->
</body>
</html>