What’s wrong with this sentence? Depending on your browser, maybe nothing at all.
Take a closer look.
Underlining was born on a typewriter. To underline text required typing the text first and then returning to the beginning of the word or line to overtype a series of underline characters. It was tedious work and the result was definitely function over form.
The ugly practice of underlining text carried over to the web and was adopted as the early moniker for identifying hyperlinks. Of all the typographic advancements such as typefaces, styling (bold, italic, etc.), font sizes and colors, underlining was given the least amount of thought. Put a line under type.
Wenting Zhang explains in less than 10 minutes what the perfect underline is on the web and how to render it more perfectly.