What is a good site for learning the rules and scoring of tennis?

I’m a total ignoramus when it comes to sports of all kinds. But I’m writing a story that involves a women’s tennis championship match in Canterbury. I’ve done some preliminary research, and I don’t get what “love” is or why the first score counts as 15 points, but the second and third scores counts as 30 and 40 points? Sites I’ve gone to assume that I’m already familiar with how the game is played, and are not helpful.