Great article but I'm confused by one bit. You say that ordering selectors from most to least efficient is good and you say that an ID selector is the most efficient. You also say that "`div #myid` will be more efficient than `#myid div` because the key selector of the first is more efficient than the key selector of the second." But that's contradicting the statement that an ID selector is the most efficient. Did you intend to say the opposite, that `#myid div` is more efficient than `div #myid`?