This book it's very interesting, I loved it.
The author go through the whole history of the artificial languages, but she does that without pedantries, all with elegance and harmony.
The book goes beyond what it might look like at first glace, because, as the author himself says, the history of the artificial languages it's strictly connected to the history itself, and the stories of their inventors.
When we study artificial languages, we study also the natural languages, 'cause their connected too.
So, through and thanks to the book, we'll know about the philosophical languages, the pictographical languages, the logical languages and so on.
It's very hard to produce an innovative language, the author says, because already the natural languages cover an enormous range of possibilities. Nevertheless, the ingenuity of the humans turned out to be extremely creative.
From Esperanto, to Klingon, to Blissymbolics, to The Lord of the Rings' languages, the history told by the author it's complete and extremely beautiful.