A few years back, a new edition of "Brief History of Time" was released: "The Illustrated Brief History of Time." (There's also an "Illustrated Universe in a Nutshell.") There are enough clever pictures and visual aids that those who had to give up on the first edition might have better luck on a second try. In particular, I recall a very nice graphic involving playing cards that went a surprisingly long way toward explaining the concept of spin.
I'm not really an average reader in this case -- I am, after all, a physicist, so I have an unfair advantage. But I read the illustrated version pretty early in my physics education, and I found it very helpful for grasping a few conceptual details that had given me a lot of trouble till then.
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Just because there's twilight doesn't mean we can't tell the difference between night and day