Check out example codes for "how to underline text in css". It will help you in understanding the concepts better.

Code Example 1

h1 {
  text-decoration: overline;
}

h2 {
  text-decoration: line-through;
}

h3 {
  text-decoration: underline;
}

h4 {
  text-decoration: underline overline;
}

Code Example 2

h3 {
  text-decoration: underline;
}

Code Example 3

h2 {
  text-decoration: line-through;
}

Code Example 4

h3 {
  text-decoration: underline;
}

Code Example 5

/* Using 'text-decoration' property with 'underline' value. we can draw underline below the text using css */
<style>
p {
  text-decoration: underline;
}
</style>
<p>Hello all Welcome here !!!</p>

Code Example 6

<!-- Using 'u' tag we can draw underline below the text in HTML -->
<p>Hello all <u>Welcome here !!!</u></p>

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