How to make a file input accept only some file types with HTML?

To make a file input accept only some file types with HTML, we set the accept attribute.

For instance, we write

<input
  type="file"
  name="foo"
  accept="application/msword, application/vnd.ms-excel, application/vnd.ms-powerpoint,
text/plain, application/pdf, image/*"
/>

to add the accept attribute and set it to a list of MIME types that the file input accepts separated by commas.