Red is a very powerful and strong color. It's associated with a variety of things, from courage and bravery to warnings and danger. It's also, of course, strongly tied to love and passion.
It's a popular color in website design, though, due to its boldness, is most commonly used as an accent color. With that said, there's no reason why it can't take on a more prominent role in a website's overall design, as demonstrated in these twenty-five awesome red websites.