Font-variant allows you to choose between normal and small-caps lettering. Small-caps are capital letters used in place of lowercase ones. The original capitals are shown as slightly bigger capitals.Do you know how can i take advantage of  font-variant  for m site?

One place where small-caps can effectively be used is in legal boilerplate where the lawyers insist that everything be capitalized for emphasis. It's a bit easier to read if you actually use small-caps. Other places where you might be tempted to SHOUT at the reader by using all capitals, you might still emphasize what you're saying but still be more readable by using small-caps. Sometimes headings <h3> etc. can look better in small-caps than all capitalized. I wouldn't do large font sizes like <h1> in small-caps, but the smaller headings can benefit from it.